Journal articles: 'Competence pilus'

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Friedrich, Alexandra, Christina Prust, Thomas Hartsch, Anke Henne, and Beate Averhoff. "Molecular Analyses of the Natural Transformation Machinery and Identification of Pilus Structures in the Extremely Thermophilic Bacterium Thermus thermophilus Strain HB27." Applied and Environmental Microbiology 68, no. 2 (February 2002): 745–55. http://dx.doi.org/10.1128/aem.68.2.745-755.2002.

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ABSTRACT Thermus thermophilus HB27, an extremely thermophilic bacterium, exhibits high competence for natural transformation. To identify genes of the natural transformation machinery of T. thermophilus HB27, we performed homology searches in the partially completed T. thermophilus genomic sequence for conserved competence genes. These analyses resulted in the detection of 28 open reading frames (ORFs) exhibiting significant similarities to known competence proteins of gram-negative and gram-positive bacteria. Disruption of 15 selected potential competence genes led to the identification of 8 noncompetent mutants and one transformation-deficient mutant with a 100-fold reduced transformation frequency. One competence protein is similar to DprA of Haemophilus influenzae, seven are similar to type IV pilus proteins of Pseudomonas aeruginosa or Neisseria gonorrhoeae (PilM, PilN, PilO, PilQ, PilF, PilC, PilD), and another deduced protein (PilW) is similar to a protein of unknown function in Deinococcus radiodurans R1. Analysis of the piliation phenotype of T. thermophilus HB27 revealed the presence of single pilus structures on the surface of the wild-type cells, whereas the noncompetent pil mutants of Thermus, with the exception of the pilF mutant, were devoid of pilus structures. These results suggest that pili and natural transformation in T. thermophilus HB27 are functionally linked.

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Long, Cynthia D., Deborah M. Tobiason, Matthew P. Lazio, Kimberly A. Kline, and H. Steven Seifert. "Low-Level Pilin Expression Allows for Substantial DNA Transformation Competence in Neisseria gonorrhoeae." Infection and Immunity 71, no. 11 (November 2003): 6279–91. http://dx.doi.org/10.1128/iai.71.11.6279-6291.2003.

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ABSTRACT The gonococcal pilus is a major virulence factor that has well-established roles in mediating epithelial cell adherence and DNA transformation. Gonococci expressing four gonococcal pilin variants with distinct piliation properties under control of the lac regulatory system were grown in different levels of the inducer isopropyl-β-d-thiogalactopyranoside (IPTG). These pilin variants expressed various levels of pilin message and pilin protein in response to the level of IPTG in the growth medium. Moreover, posttranslational modifications of the variant pilin proteins were detected, including S-pilin production and glycosylation. The ratio of the modified and unmodified pilin forms did not substantially change with different levels of pilin expression, showing that these modifications are not linked to pilin expression levels. DNA transformation competence was also influenced by IPTG levels in the growth medium. Substantial increases in transformation competence over an isogenic, nonpiliated mutant were observed when limited amounts of three of the pilin variants were expressed. Immunoelectron microscopy showed that when limited amounts of pilin are expressed, pili are rare and do not explain the pilin-dependent transformation competence. This pilin-dependent transformation competence required prepilin processing, the outer membrane secretin PilQ, and the twitching-motility-regulating protein PilT. These requirements show that a fully functional pilus assembly apparatus is required for DNA uptake when limited pilin is produced. We conclude that the pilus assembly apparatus functions to import DNA into the bacterial cell in a pilin-dependent manner but that extended pili are not required for transformation competence.

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Graupner, Stefan, Nicole Weger, Monika Sohni, and Wilfried Wackernagel. "Requirement of Novel Competence Genes pilT andpilU of Pseudomonas stutzeri for Natural Transformation and Suppression of pilT Deficiency by a Hexahistidine Tag on the Type IV Pilus Protein PilAI." Journal of Bacteriology 183, no. 16 (August 15, 2001): 4694–701. http://dx.doi.org/10.1128/jb.183.16.4694-4701.2001.

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ABSTRACT The ubiquitous species Pseudomonas stutzeri has type IV pili, and these are essential for the natural transformation of the cells. An absolute transformation-deficient mutant obtained after transposon mutagenesis had an insertion in a gene which was termedpilT. The deduced amino acid sequence has identity with PilT of Pseudomonas aeruginosa (94%), Neisseria gonorrhoeae (67%), and other gram-negative species and it contains a nucleotide-binding motif. The mutant was hyperpiliated but defective for further pilus-associated properties, such as twitching motility and plating of pilus-specific phage PO4. [3H]thymidine-labeled DNA was bound by the mutant but not taken up. Downstream of pilT a gene, termedpilU, coding for a putative protein with 88% amino acid identity with PilU of P. aeruginosa was identified. Insertional inactivation did not affect piliation, twitching motility, or PO4 infection but reduced transformation to about 10%. The defect was fully complemented by PilU of nontransformable P. aeruginosa. When thepilAI gene (coding for the type IV pilus prepilin) was manipulated to code for a protein in which the six C-terminal amino acids were replaced by six histidine residues and then expressed from a plasmid, it gave a nonpiliated and twitching motility-defective phenotype in pilAI::Gmr cells but allowed transformability. Moreover, the mutant allele suppressed the absolute transformation deficiency caused by the pilT mutation. Considering the hypothesized role of pilT + in pilus retraction and the presumed requirement of retraction for DNA uptake, it is proposed that the pilT-independent transformation is promoted by PilA mutant protein either as single molecules or as minimal pilin assembly structures in the periplasm which may resemble depolymerized pili and that these cause the outer membrane pores to open for DNA entry.

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Friedrich, Alexandra, Judit Rumszauer, Anke Henne, and Beate Averhoff. "Pilin-Like Proteins in the Extremely Thermophilic Bacterium Thermus thermophilus HB27: Implication in Competence for Natural Transformation and Links to Type IV Pilus Biogenesis." Applied and Environmental Microbiology 69, no. 7 (July 2003): 3695–700. http://dx.doi.org/10.1128/aem.69.7.3695-3700.2003.

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ABSTRACT The extreme thermophile Thermus thermophilus HB27 exhibits high frequencies of natural transformation. Although we recently reported identification of the first competence genes in Thermus, the molecular basis of DNA uptake is unknown. A pilus-like structure is assumed to be involved. Twelve genes encoding prepilin-like proteins were identified in three loci in the genome of T. thermophilus. Mutational analyses, described in this paper, revealed that one locus, which contains four genes that encode prepilin-like proteins (pilA1 to pilA4), is essential for natural transformation. Additionally, comZ, a new competence gene with no similarity to known genes, was identified. Analysis of the piliation phenotype revealed wild-type piliation of a pilA1-pilA3Δkat mutant and a comZ mutant, whereas a pilA4 mutant was found to be completely devoid of pilus structures. These findings, together with the significant similarity of PilA4 to prepilins, led to the conclusion that the T. thermophilus pilus structures are type IV pili. Furthermore, the loss of the transformation and piliation phenotype in the pilA4 mutant suggests that type IV pili are implicated in natural transformation of T. thermophilus HB27.

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Fussenegger, Martin, Thomas Rudel, Roland Barten, Roland Ryll, and Thomas F. Meyer. "Transformation competence and type-4 pilus biogenesis in Neisseriagonorrhoeae – areview." Gene 192, no. 1 (June 1997): 125–34. http://dx.doi.org/10.1016/s0378-1119(97)00038-3.

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Muschiol, Sandra, Simon Erlendsson, Marie-Stephanie Aschtgen, Vitor Oliveira, Peter Schmieder, Casper de Lichtenberg, Kaare Teilum, Thomas Boesen, Umit Akbey, and Birgitta Henriques-Normark. "Structure of the competence pilus major pilin ComGC inStreptococcus pneumoniae." Journal of Biological Chemistry 292, no. 34 (June 28, 2017): 14134–46. http://dx.doi.org/10.1074/jbc.m117.787671.

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Dubnau, David, and Melanie Blokesch. "Mechanisms of DNA Uptake by Naturally Competent Bacteria." Annual Review of Genetics 53, no. 1 (December 3, 2019): 217–37. http://dx.doi.org/10.1146/annurev-genet-112618-043641.

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Transformation is a widespread mechanism of horizontal gene transfer in bacteria. DNA uptake to the periplasmic compartment requires a DNA-uptake pilus and the DNA-binding protein ComEA. In the gram-negative bacteria, DNA is first pulled toward the outer membrane by retraction of the pilus and then taken up by binding to periplasmic ComEA, acting as a Brownian ratchet to prevent backward diffusion. A similar mechanism probably operates in the gram-positive bacteria as well, but these systems have been less well characterized. Transport, defined as movement of a single strand of transforming DNA to the cytosol, requires the channel protein ComEC. Although less is understood about this process, it may be driven by proton symport. In this review we also describe various phenomena that are coordinated with the expression of competence for transformation, such as fratricide, the kin-discriminatory killing of neighboring cells, and competence-mediated growth arrest.

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Villar, Maria T., Rona L. Hirschberg, and Michael R. Schaefer. "Role of the Eikenella corrodens pilALocus in Pilus Function and Phase Variation." Journal of Bacteriology 183, no. 1 (January 1, 2001): 55–62. http://dx.doi.org/10.1128/jb.183.1.55-62.2001.

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ABSTRACT The human pathogen Eikenella corrodens expresses type IV pili and exhibits a phase variation involving the irreversible transition from piliated to nonpiliated variants. On solid medium, piliated variants form small (S-phase), corroding colonies whereas nonpiliated variants form large (L-phase), noncorroding colonies. We are studying pilus structure and function in the clinical isolateE. corrodens VA1. Earlier work defined the pilAlocus which includes pilA1, pilA2,pilB, and hagA. Both pilA1 andpilA2 predict a type IV pilin, whereas pilBpredicts a putative pilus assembly protein. The role ofhagA has not been clearly established. That work also confirmed that pilA1 encodes the major pilus protein in this strain and showed that the phase variation involves a posttranslational event in pilus formation. In this study, the function of the individual genes comprising the pilA locus was examined using a recently developed protocol for targeted interposon mutagenesis of S-phase variant VA1-S1. Different pilAmutants were compared to S-phase and L-phase variants for several distinct aspects of phase variation and type IV pilus biosynthesis and function. S-phase cells were characterized by surface pili, competence for natural transformation, and twitching motility, whereas L-phase cells lacked these features. Inactivation of pilA1 yielded a mutant that was phenotypically indistinguishable from L-phase variants, showing that native biosynthesis of the type IV pilus in strain VA1 is dependent on expression of pilA1 and proper export and assembly of PilA1. Inactivation of pilA2 yielded a mutant that was phenotypically indistinguishable from S-phase variants, indicating that pilA2 is not essential for biosynthesis of functionally normal pili. A mutant inactivated forpilB was deficient for twitching motility, suggesting a role for PilB in this pilus-related phenomenon. Inactivation ofhagA, which may encode a tellurite resistance protein, had no effect on pilus structure or function.

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Lång, Emma, Kristine Haugen, Burkhard Fleckenstein, Håvard Homberset, Stephan A. Frye, Ole Herman Ambur, and Tone Tønjum. "Identification of neisserial DNA binding components." Microbiology 155, no. 3 (March 1, 2009): 852–62. http://dx.doi.org/10.1099/mic.0.022640-0.

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Neisseria meningitidis, a causative agent of meningitis and septicaemia, expresses type IV pili, a feature correlating with the uptake of exogenous DNA from the environment by natural transformation. The outer membrane complex PilQ, through which pili are extruded and retracted, has previously been shown to bind DNA in its pore region. In order to further elucidate how DNA is transported across the membranes, we searched for DNA binding proteins within the meningococcal inner membrane. Inner membrane fractions from a panel of neisserial strains were subjected to a solid-phase overlay assay with DNA substrates, and MS was subsequently employed to identify proteins that bind DNA. A number of DNA binding components were detected, including the pilus biogenesis component PilG, the competence protein ComL, and the cell division ATP-binding protein FtsE, as well as two hypothetical proteins. The DNA binding activity of these components was not dependent on the presence of the neisserial DNA uptake sequence. Null mutants, corresponding to each of the proteins identified, were constructed to assess their phenotypes. Only mutants defective in pilus biogenesis were non-competent and non-piliated. The DNA binding activity of the pilus biogenesis components PilQ and PilG and the phenotypes of their respective null mutants suggest that these proteins are directly involved as players in natural transformation, and not only indirectly, through pilus biogenesis.

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Laurenceau, Raphaël, Petya V. Krasteva, Amy Diallo, Sahra Ouarti, Magalie Duchateau, Christian Malosse, Julia Chamot-Rooke, and Rémi Fronzes. "Conserved Streptococcus pneumoniae Spirosomes Suggest a Single Type of Transformation Pilus in Competence." PLOS Pathogens 11, no. 4 (April 15, 2015): e1004835. http://dx.doi.org/10.1371/journal.ppat.1004835.

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Shaw, A. Joe, David A. Hogsett, and Lee R. Lynd. "Natural Competence in Thermoanaerobacter and Thermoanaerobacterium Species." Applied and Environmental Microbiology 76, no. 14 (May 14, 2010): 4713–19. http://dx.doi.org/10.1128/aem.00402-10.

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ABSTRACT Low-G+C thermophilic obligate anaerobes in the class Clostridia are considered among the bacteria most resistant to genetic engineering due to the difficulty of introducing foreign DNA, thus limiting the ability to study and exploit their native hydrolytic and fermentative capabilities. Here, we report evidence of natural genetic competence in 13 Thermoanaerobacter and Thermoanaerobacterium strains previously believed to be difficult to transform or genetically recalcitrant. In Thermoanaerobacterium saccharolyticum JW/SL-YS485, natural competence-mediated DNA incorporation occurs during the exponential growth phase with both replicating plasmid and homologous recombination-based integration, and circular or linear DNA. In T. saccharolyticum, disruptions of genes similar to comEA, comEC, and a type IV pilus (T4P) gene operon result in strains unable to incorporate further DNA, suggesting that natural competence occurs via a conserved Gram-positive mechanism. The relative ease of employing natural competence for gene transfer should foster genetic engineering in these industrially relevant organisms, and understanding the mechanisms underlying natural competence may be useful in increasing the applicability of genetic tools to difficult-to-transform organisms.

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Link, Caroline, Sandra Eickernjäger, Dirk Porstendörfer, and Beate Averhoff. "Identification and Characterization of a Novel Competence Gene,comC, Required for DNA Binding and Uptake inAcinetobacter sp. Strain BD413." Journal of Bacteriology 180, no. 6 (March 15, 1998): 1592–95. http://dx.doi.org/10.1128/jb.180.6.1592-1595.1998.

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ABSTRACT A gene (comC) essential for natural transformation was identified in Acinetobacter sp. strain BD413. ComC has a typical leader sequence and is similar to different type IV pilus assembly factors. A comC mutant (T308) is not able to bind or take up DNA but exhibits a piliation phenotype indistinguishable from the transformation wild type as revealed by electron microscopy.

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Obergfell, Kyle P., and H. Steven Seifert. "The Pilin N-terminal Domain Maintains Neisseria gonorrhoeae Transformation Competence during Pilus Phase Variation." PLOS Genetics 12, no. 5 (May 23, 2016): e1006069. http://dx.doi.org/10.1371/journal.pgen.1006069.

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Albiger, Barbara, Linda Johansson, and Ann-Beth Jonsson. "Lipooligosaccharide-Deficient Neisseria meningitidis Shows Altered Pilus-Associated Characteristics." Infection and Immunity 71, no. 1 (January 2003): 155–62. http://dx.doi.org/10.1128/iai.71.1.155-162.2003.

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ABSTRACT Molecular interaction between host mucosal surfaces and outer membrane components of microbes is crucial in the infection process. The outer membrane of pathogenic Neisseria contains surface molecules such as pili, PilC, and Opa and a monolayer of lipooligosaccharide (LOS), all of which are involved in the interaction with host cells. Pili mediate the initial attachment to human epithelial cells, which is followed by tight contact between bacteria and the eucaryotic cells, leading to bacterial invasion. To further examine the basis for bacterium-host cell contact, we constructed an LOS-deficient Neisseria meningitidis serogroup C mutant. LOS deficiency was without exception accompanied by altered colony opacity and morphology, which most likely represented an “on” switch for Opa540 expression, and by reduced levels of the iron-regulated proteins FetA and FbpA. We show here that LOS is essential for pilus-associated adherence but dispensable for fiber formation and twitching motility. The absence of attachment to epithelial cells could not be attributed to altered levels of piliation or defects in the pilus adhesion phenotype. Further, LOS mutants do not invade host cells and have lost the natural competence for genetic transformation.

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Luke, Nicole R., Amy J. Howlett, Jianqiang Shao, and Anthony A. Campagnari. "Expression of Type IV Pili by Moraxella catarrhalis Is Essential for Natural Competence and Is Affected by Iron Limitation." Infection and Immunity 72, no. 11 (November 2004): 6262–70. http://dx.doi.org/10.1128/iai.72.11.6262-6270.2004.

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ABSTRACT Type IV pili, filamentous surface appendages primarily composed of a single protein subunit termed pilin, play a crucial role in the initiation of disease by a wide range of pathogenic bacteria. Although previous electron microscopic studies suggested that pili might be present on the surface of Moraxella catarrhalis isolates, detailed molecular and phenotypic analyses of these structures have not been reported to date. We identified and cloned the M. catarrhalis genes encoding PilA, the major pilin subunit, PilQ, the outer membrane secretin through which the pilus filament is extruded, and PilT, the NTPase that mediates pilin disassembly and retraction. To initiate investigation of the role of this surface organelle in pathogenesis, isogenic pilA, pilT, and pilQ mutants were constructed in M. catarrhalis strain 7169. Comparative analyses of the wild-type 7169 strain and three isogenic pil mutants demonstrated that M. catarrhalis expresses type IV pili that are essential for natural genetic transformation. Our studies suggest type IV pilus production by M. catarrhalis is constitutive and ubiquitous, although pilin expression was demonstrated to be iron responsive and Fur regulated. These data indicate that additional studies aimed at elucidating the prevalence and role of type IV pili in the pathogenesis and host response to M. catarrhalis infections are warranted.

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Cai, Lulu, Mukesh Jain, Marta Sena-Vélez, Kathryn M. Jones, Laura A. Fleites, Michelle Heck, and Dean W. Gabriel. "Tad pilus-mediated twitching motility is essential for DNA uptake and survival of Liberibacters." PLOS ONE 16, no. 10 (October 13, 2021): e0258583. http://dx.doi.org/10.1371/journal.pone.0258583.

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Axenically cultured Liberibacter crescens (Lcr) is a closely related surrogate for uncultured plant pathogenic species of the genus Liberibacter, including ‘Candidatus L. asiaticus’ (CLas) and ‘Ca. L. solanacearum’ (CLso). All Liberibacters encode a completely conserved gene repertoire for both flagella and Tad (Tight Adherence) pili and all are missing genes critical for nucleotide biosynthesis. Both flagellar swimming and Tad pilus-mediated twitching motility in Lcr were demonstrated for the first time. A role for Tad pili in the uptake of extracellular dsDNA for food in Liberibacters was suspected because both twitching and DNA uptake are impossible without repetitive pilus extension and retraction, and no genes encoding other pilus assemblages or mechanisms for DNA uptake were predicted to be even partially present in any of the 35 fully sequenced Liberibacter genomes. Insertional mutations of the Lcr Tad pilus genes cpaA, cpaB, cpaE, cpaF and tadC all displayed such severely reduced growth and viability that none could be complemented. A mutation affecting cpaF (motor ATPase) was further characterized and the strain displayed concomitant loss of twitching, viability and reduced periplasmic uptake of extracellular dsDNA. Mutations of comEC, encoding the inner membrane competence channel, had no effect on either motility or growth but completely abolished natural transformation in Lcr. The comEC mutation was restored by complementation using comEC from Lcr but not from CLas strain psy62 or CLso strain RS100, indicating that unlike Lcr, these pathogens were not naturally competent for transformation. This report provides the first evidence that the Liberibacter Tad pili are dynamic and essential for both motility and DNA uptake, thus extending their role beyond surface adherence.

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Long, Cynthia D., Stanley F. Hayes, Jos P. M. van Putten, Hillery A. Harvey, Michael A. Apicella, and H. Steven Seifert. "Modulation of Gonococcal Piliation by Regulatable Transcription of pilE." Journal of Bacteriology 183, no. 5 (March 1, 2001): 1600–1609. http://dx.doi.org/10.1128/jb.183.5.1600-1609.2001.

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ABSTRACT The gonococcal pilus, a member of the type IV family of pili, is composed of numerous monomers of the pilin protein and plays an important role in the initiation of disease by providing the primary attachment of the bacterial cell to human mucosal tissues. Piliation also correlates with efficient DNA transformation. To investigate the relationships between these pilus-related functions, the piliation state, and the availability of pilin, we constructed a derivative of MS11-C9 (ΔpilE1) in which the lacIOPregulatory sequences control pilE transcription. In this strain, MS11-C9.10, the steady-state levels of pilin mRNA and protein directly correlate with the concentration of IPTG (isopropyl-β-d-thiogalactopyranoside) in the growth medium and can reach near-wild-type levels of expression. Transmission electron microscopy (TEM) demonstrated that the number of pili per cell correlated with the steady-state expression levels: at a low level of transcription, single long pili were observed; at a moderate expression level, many singular and bundled pili were expressed; and upon full gene expression, increased lateral association between pili was observed. Analysis of pilus assembly by TEM and epithelial cell adherence over a time course of induction demonstrated that pili were expressed as early as 1 h postinduction. Analysis at different steady-state levels of transcription demonstrated that DNA transformation efficiency and adherence of MS11-C9.10 to transformed and primary epithelial cells also correlated with the level of piliation. These data show that modulation of the level ofpilE transcription, without a change in pilEsequence, can alter the number of pili expressed per cell, pilus bundling, DNA transformation competence, and epithelial cell adherence of the gonococcus.

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Salzer, Ralf, Friederike Joos, and Beate Averhoff. "Different effects of MglA and MglB on pilus-mediated functions and natural competence in Thermus thermophilus." Extremophiles 19, no. 2 (December 4, 2014): 261–67. http://dx.doi.org/10.1007/s00792-014-0711-4.

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VanWagoner, Timothy M., Paul W. Whitby, Daniel J. Morton, Thomas W. Seale, and Terrence L. Stull. "Characterization of Three New Competence-Regulated Operons in Haemophilus influenzae." Journal of Bacteriology 186, no. 19 (October 1, 2004): 6409–21. http://dx.doi.org/10.1128/jb.186.19.6409-6421.2004.

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ABSTRACT Haemophilus influenzae is one of a growing number of bacteria in which the natural ability to uptake exogenous DNA for potential genomic transformation has been recognized. To date, several operons involved in transformation in this organism have been described. These operons are characterized by a conserved 22-bp regulatory element upstream of the first gene and are induced coincident with transfer from rich to nutrient-depleted media. The previously identified operons comprised genes encoding proteins that include members of the type II secretion system and type IV pili, shown to be essential for transformation in other bacteria, and other proteins previously identified as required for transformation in H. influenzae. In the present study, three novel competence operons were identified by comparative genomics and transcriptional analysis. These operons have been further characterized by construction of null mutants and examination of the resulting transformation phenotypes. The putative protein encoded by the HI0366 gene was shown to be essential for DNA uptake, but not binding, and is homologous to a protein shown to be required for pilus biogenesis and twitching motility in Pseudomonas aeruginosa. An insertion in HI0939 abolished both DNA binding and uptake. The predicted product of this gene shares characteristics with PulJ, a pseudopilin involved in pullulanase export in Klebsiella oxytoca.

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Porstendörfer, Dirk, Olivia Gohl, Frank Mayer, and Beate Averhoff. "ComP, a Pilin-Like Protein Essential for Natural Competence in Acinetobacter sp. Strain BD413: Regulation, Modification, and Cellular Localization." Journal of Bacteriology 182, no. 13 (July 1, 2000): 3673–80. http://dx.doi.org/10.1128/jb.182.13.3673-3680.2000.

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ABSTRACT We recently identified a pilin-like competence factor, ComP, which is essential for natural transformation of the gram-negative soil bacterium Acinetobacter sp. strain BD413. Here we demonstrate that transcription and synthesis of the pilin-like competence factor ComP are maximal in the late stationary growth phase, whereas competence is induced immediately after inoculation of a stationary-phase culture into fresh medium. Western blot analyses revealed three forms of ComP, one with an apparent molecular mass of 15 kDa, which correlates with the molecular mass deduced from the DNA sequence, one 20-kDa form, which was found to be glycosylated, and one 23-kDa form. The glycosylation of ComP was not required for its function in DNA binding and uptake. The 20-kDa form was present in the cytoplasmic membrane, the periplasm, and the outer membrane, whereas the 23-kDa form was located in the outer membrane and might be due to a further modification. Immunological data suggest that ComP is not a subunit of the pilus structures. Possible functions of ComP in the DNA transformation machinery of Acinetobacter sp. strain BD413 are discussed.

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Gohl, Olivia, Alexandra Friedrich, Michael Hoppert, and Beate Averhoff. "The Thin Pili of Acinetobacter sp. Strain BD413 Mediate Adhesion to Biotic and Abiotic Surfaces." Applied and Environmental Microbiology 72, no. 2 (February 2006): 1394–401. http://dx.doi.org/10.1128/aem.72.2.1394-1401.2006.

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ABSTRACT Two structurally different appendages, thin and thick pili, are found in members of the genus Acinetobacter. The presence of pilus structures correlates with different phenotypes, such as adherence to surfaces, a trait not only observed in pathogenic Acinetobacter species, as well as motility. However, their distinct individual roles were unknown. To characterize the role of different pili in the physiology of Acinetobacter, we isolated the thin pili from the cell surface of Acinetobacter sp. strain BD413 (recently recognized as representative of Acinetobacter baylyi), a soil bacterium that rapidly takes up naked DNA from its environment. Electron microcopy revealed that the pilus has an external diameter of 2 to 3 nm for single filaments. The filaments are packed into right-handed bundles. The major protein constituting the pilus was purified, and the encoding gene, acuA, was cloned. AcuA was found to be weakly related to the structural subunit of F17 pili of Escherichia coli. Analyses of the acuA flanking DNA region led to the identification of three closely associated genes, acuD, acuC, and acuG, whose deduced proteins are similar to chaperone, usher, and adhesin of F17-related pili, respectively. Transcriptional analyses revealed that acuA expression is maximal in the late-stationary-growth phase. Mutation of acuA led to a loss of thin pili and concomitantly loss of adhesion to polystyrene and erythrocytes but not loss of competence. Therefore, thin pili of Acinetobacter sp. strain BD413 are suggested to be assembled by the chaperone/usher pathway and are involved in adherence to biotic and abiotic surfaces.

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Park, Hae-Sun Moon, Matthew Wolfgang, and Michael Koomey. "Modification of Type IV Pilus-Associated Epithelial Cell Adherence and Multicellular Behavior by the PilU Protein of Neisseria gonorrhoeae." Infection and Immunity 70, no. 7 (July 2002): 3891–903. http://dx.doi.org/10.1128/iai.70.7.3891-3903.2002.

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ABSTRACT Expression of type IV pili (Tfp) correlates with the ability of Neisseria gonorrhoeae to colonize the human host, as well as with adherence to human epithelial tissue, twitching motility, competence for natural transformation, and autoagglutination. N. gonorrhoeae PilF (required for Tfp biogenesis) and PilT (required for twitching motility and transformation) share significant identities with members of a family of putative ATPases involved in membrane trafficking of macromolecules. An open reading frame downstream of the pilT locus encoding a 408-amino-acid protein with 33% identity with the gonococcal PilT protein and 45% identity with the PilU protein in Pseudomonas aeruginosa was characterized, and the corresponding gene was designated pilU. Unlike N. gonorrhoeae pilT mutants, pilU mutants express twitching motility and are competent for DNA transformation. However, loss-of-function mutations in pilU increased bacterial adherence to ME-180 human epithelial cells eightfold and disrupted in vitro Tfp-associated autoagglutination. Comparative alignment of N. gonorrhoeae PilU with other members of the TrbB-like family of traffic ATPases revealed a conserved carboxy-terminal domain unique to family members which are not essential for Tfp biogenesis but which specifically modify Tfp-associated phenotypes. Studies of the pilT-pilU locus by using Northern blotting, transcriptional fusions, and reverse transcription-PCR showed that the two genes encoding closely related proteins with dissimilar effects on Tfp phenotypes are transcribed from a single promoter.

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Ryll, Roland R., Thomas Rudel, Ina Scheuerpflug, Roland Barten, and Thomas F. Meyer. "PilC of Neisseria meningitidis is involved in class II pilus formation and restores pilus assembly, natural transformation competence and adherence to epithelial cells in PilC‐deficient gonococci." Molecular Microbiology 23, no. 5 (March 1997): 879–92. http://dx.doi.org/10.1046/j.1365-2958.1997.2631630.x.

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Stone, Barbara J., and Yousef Abu Kwaik. "Natural Competence for DNA Transformation by Legionella pneumophila and Its Association with Expression of Type IV Pili." Journal of Bacteriology 181, no. 5 (March 1, 1999): 1395–402. http://dx.doi.org/10.1128/jb.181.5.1395-1402.1999.

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ABSTRACT We have recently described the expression of two pili of different lengths on the surface of Legionella pneumophila (B. J. Stone and Y. Abu Kwaik, Infect. Immun. 66:1768–1775, 1998). Production of long pili requires a functional pilE L locus, encoding a type IV pilin protein. Since type IV pili in Neisseria gonorrhoeaeare associated with competence for DNA transformation, we examined the competence of L. pneumophila for DNA transformation under conditions that allowed the expression of type IV pili. We show that L. pneumophila is naturally competent for DNA transformation by isogenic chromosomal DNA and by plasmid DNA containing L. pneumophila DNA. Many different L. pneumophila loci are able to transform L. pneumophilaafter addition of plasmid DNA, including gspA,ppa, asd, and pilE L. The transformation frequency is reduced when competing DNA containing either L. pneumophila DNA or vector sequences is added to the bacteria, suggesting that uptake-specific sequences may not be involved in DNA uptake. Competence for DNA transformation correlates with expression of the type IV pili, and apilE L mutant defective in expression of type IV pili is not competent for DNA transformation. Complementation of the mutant for competence is restored by the reintroduction of a cosmid that restores production of type IV pili. Minimal competence is restored to the mutant by introduction of pilE Lalone. We conclude that competence for DNA transformation in L. pneumophila is associated with expression of the type IV pilus and results in recombination of L. pneumophila DNA into the chromosome. Since expression of type IV pili also facilitates attachment of L. pneumophila to mammalian cells and protozoa, we designated the type IV pili CAP (for competence- and adherence-associated pili).

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Chen, Inês, and Emil C. Gotschlich. "ComE, a Competence Protein from Neisseria gonorrhoeae with DNA-Binding Activity." Journal of Bacteriology 183, no. 10 (May 15, 2001): 3160–68. http://dx.doi.org/10.1128/jb.183.10.3160-3168.2001.

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ABSTRACT Neisseria gonorrhoeae is naturally able to take up exogenous DNA and undergo genetic transformation. This ability correlates with the presence of functional type IV pili, and uptake of DNA is dependent on the presence of a specific 10-bp sequence. Among the known competence factors in N. gonorrhoeae, none has been shown to interact with the incoming DNA. Here we describe ComE, a DNA-binding protein involved in neisserial competence. The genecomE was identified through similarity searches in the gonococcal genome sequence, using as the query ComEA, the DNA receptor in competent Bacillus subtilis. The gene comEis present in four identical copies in the genomes of both N. gonorrhoeae and Neisseria meningitidis, located downstream of each of the rRNA operons. Single-copy deletion ofcomE in N. gonorrhoeae did not have a measurable effect on competence, whereas serial deletions led to gradual decrease in transformation frequencies, reaching a 4 × 104-fold reduction when all copies were deleted. Transformation deficiency correlated with impaired ability to take up exogenous DNA; however, the mutants presented normal piliation and twitching motility phenotype. The product of comE has 99 amino acids, with a predicted signal peptide; by immunodetection, a 8-kDa protein corresponding to processed ComE was observed in different strains of N. gonorrhoeae and N. meningitidis. Recombinant His-tagged ComE showed DNA binding activity, without any detectable sequence specificity. Thus, we identified a novel gonococcal DNA-binding competence factor which is necessary for DNA uptake and does not affect pilus biogenesis or function.

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Sheppard, Devon, Jamie-Lee Berry, Rémi Denise, Eduardo P. C. Rocha, Steve Matthews, and Vladimir Pelicic. "The major subunit of widespread competence pili exhibits a novel and conserved type IV pilin fold." Journal of Biological Chemistry 295, no. 19 (April 9, 2020): 6594–604. http://dx.doi.org/10.1074/jbc.ra120.013316.

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Type IV filaments (T4F), which are helical assemblies of type IV pilins, constitute a superfamily of filamentous nanomachines virtually ubiquitous in prokaryotes that mediate a wide variety of functions. The competence (Com) pilus is a widespread T4F, mediating DNA uptake (the first step in natural transformation) in bacteria with one membrane (monoderms), an important mechanism of horizontal gene transfer. Here, we report the results of genomic, phylogenetic, and structural analyses of ComGC, the major pilin subunit of Com pili. By performing a global comparative analysis, we show that Com pili genes are virtually ubiquitous in Bacilli, a major monoderm class of Firmicutes. This also revealed that ComGC displays extensive sequence conservation, defining a monophyletic group among type IV pilins. We further report ComGC solution structures from two naturally competent human pathogens, Streptococcus sanguinis (ComGCSS) and Streptococcus pneumoniae (ComGCSP), revealing that this pilin displays extensive structural conservation. Strikingly, ComGCSS and ComGCSP exhibit a novel type IV pilin fold that is purely helical. Results from homology modeling analyses suggest that the unusual structure of ComGC is compatible with helical filament assembly. Because ComGC displays such a widespread distribution, these results have implications for hundreds of monoderm species.

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Aas, Finn Erik, Matthew Wolfgang, Stephan Frye, Steven Dunham, Cecilia Løvold, and Michael Koomey. "Competence for natural transformation in Neisseria gonorrhoeae: components of DNA binding and uptake linked to type IV pilus expression." Molecular Microbiology 46, no. 3 (October 31, 2002): 749–60. http://dx.doi.org/10.1046/j.1365-2958.2002.03193.x.

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Frye, Stephan A., Reza Assalkhou, Richard F. Collins, Robert C. Ford, Christoffer Petersson, Jeremy P. Derrick, and Tone Tønjum. "Topology of the outer-membrane secretin PilQ from Neisseria meningitidis." Microbiology 152, no. 12 (December 1, 2006): 3751–64. http://dx.doi.org/10.1099/mic.0.2006/000315-0.

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Neisseria meningitidis is the causative agent of epidemic meningococcal meningitis and septicaemia. Type IV pili are surface organelles that mediate a variety of functions, including adhesion, twitching motility, and competence for DNA binding and uptake in transformation. The secretin PilQ is required for type IV pilus expression at the cell surface, and forms a dodecameric cage-like macromolecular complex in the meningococcal outer membrane. PilQ-null mutants are devoid of surface pili, and prevailing evidence suggests that the PilQ complex facilitates extrusion and retraction of type IV pili across the outer membrane. Defining the orientation of the meningococcal PilQ complex in the membrane is a prerequisite for understanding the structure–function relationships of this important protein in pilus biology. In order to begin to define the topology of the PilQ complex in the outer membrane, polyhistidine insertions in N- and C-terminal regions of PilQ were constructed, and their subcellular locations examined. Notably, the insertion epitopes at residues 205 and 678 were located within the periplasm, whereas residue 656 was exposed at the outer surface of the outer membrane. Using electron microscopy with Ni-NTA gold labelling, it was demonstrated that the insertion at residue 205 within the N-terminus mapped to a site on the arm-like features of the 3D structure of the PilQ multimer. Interestingly, mutation of the same region gave rise to an increase in vancomycin permeability through the PilQ complex. The results yield novel information on the PilQ N-terminal location and function in the periplasm, and reveal a complex organization of the membrane-spanning secretin in vivo.

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Benam, Afsaneh V., Emma Lång, Kristian Alfsnes, Burkhard Fleckenstein, Alexander D. Rowe, Eirik Hovland, Ole Herman Ambur, Stephan A. Frye, and Tone Tønjum. "Structure–function relationships of the competence lipoprotein ComL and SSB in meningococcal transformation." Microbiology 157, no. 5 (May 1, 2011): 1329–42. http://dx.doi.org/10.1099/mic.0.046896-0.

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Neisseria meningitidis, the meningococcus, is naturally competent for transformation throughout its growth cycle. The uptake of exogenous DNA into the meningococcus cell during transformation is a multi-step process. Beyond the requirement for type IV pilus expression for efficient transformation, little is known about the neisserial proteins involved in DNA binding, uptake and genome integration. This study aimed to identify and characterize neisserial DNA binding proteins in order to further elucidate the multi-factorial transformation machinery. The meningococcus inner membrane and soluble cell fractions were searched for DNA binding components by employing 1D and 2D gel electrophoresis approaches in combination with a solid-phase overlay assay with DNA substrates. Proteins that bound DNA were identified by MS analysis. In the membrane fraction, multiple components bound DNA, including the neisserial competence lipoprotein ComL. In the soluble fraction, the meningococcus orthologue of the single-stranded DNA binding protein SSB was predominant. The DNA binding activity of the recombinant ComL and SSB proteins purified to homogeneity was verified by electromobility shift assay, and the ComL–DNA interaction was shown to be Mg2+-dependent. In 3D models of the meningococcus ComL and SSB predicted structures, potential DNA binding sites were suggested. ComL was found to co-purify with the outer membrane, directly interacting with the secretin PilQ. The combined use of 1D/2D solid-phase overlay assays with MS analysis was a useful strategy for identifying DNA binding components. The ComL DNA binding properties and outer membrane localization suggest that this lipoprotein plays a direct role in neisserial transformation, while neisserial SSB is a DNA binding protein that contributes to the terminal part of the transformation process.

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Salomonsson, Emelie, Åke Forsberg, Norbert Roos, Claudia Holz, Berenike Maier, Michael Koomey, and Hanne C. Winther-Larsen. "Functional analyses of pilin-like proteins from Francisella tularensis: complementation of type IV pilus phenotypes in Neisseria gonorrhoeae." Microbiology 155, no. 8 (August 1, 2009): 2546–59. http://dx.doi.org/10.1099/mic.0.028183-0.

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Accumulating evidence from a number of studies strongly suggests that proteins orthologous to those involved in type IV pili (Tfp) assembly and function are required for Francisella pathogenicity. However, the molecular mechanisms by which the components exert their influence on virulence remain poorly understood. Owing to the conservation and promiscuity of Tfp biogenesis machineries, expression of Tfp pilins in heterologous species has been used successfully to analyse organelle structure–function relationships. In this study we expressed a number of Francisella pilin genes in the Tfp-expressing pathogen Neisseria gonorrhoeae lacking its endogenous pilin subunit. Two gene products, the orthologous PilA proteins from Francisella tularensis subspecies tularensis and novicida, were capable of restoring the expression of Tfp-like appendages that were shown to be dependent upon the neisserial Tfp biogenesis machinery for surface localization. Expression of Francisella PilA pilins also partially restored competence for natural transformation in N. gonorrhoeae. This phenotype was not complemented by expression of the PulG and XcpT proteins, which are equivalent components of the related type II protein secretion system. Taken together, these findings provide compelling, although indirect, evidence of the potential for Francisella PilA proteins to express functional Tfp.

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Yaman, Deniz, and Beate Averhoff. "Functional dissection of structural regions of the Thermus thermophilus competence protein PilW: Implication in secretin complex stability, natural transformation and pilus functions." Biochimica et Biophysica Acta (BBA) - Biomembranes 1863, no. 10 (October 2021): 183666. http://dx.doi.org/10.1016/j.bbamem.2021.183666.

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Renda, Brian A., Cindy Chan, Kristin N. Parent, and Jeffrey E. Barrick. "Emergence of a Competence-Reducing Filamentous Phage from the Genome of Acinetobacter baylyi ADP1." Journal of Bacteriology 198, no. 23 (September 19, 2016): 3209–19. http://dx.doi.org/10.1128/jb.00424-16.

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ABSTRACTBacterial genomes commonly contain prophage sequences as a result of past infections with lysogenic phages. Many of these integrated viral sequences are believed to be cryptic, but prophage genes are sometimes coopted by the host, and some prophages may be reactivated to form infectious particles when cells are stressed or mutate. We found that a previously uncharacterized filamentous phage emerged from the genome ofAcinetobacter baylyiADP1 during a laboratory evolution experiment. This phage has a genetic organization similar to that of theVibrio choleraeCTXϕ phage. The emergence of the ADP1 phage was associated with the evolution of reduced transformability in our experimental populations, so we named it thecompetence-reducingacinetobacter phage (CRAϕ). Knocking out ADP1 genes required for competence leads to resistance to CRAϕ infection. Although filamentous bacteriophages are known to target type IV pili, this is the first report of a phage that apparently uses a competence pilus as a receptor.A. baylyimay be especially susceptible to this route of infection because every cell is competent during normal growth, whereas competence is induced only under certain environmental conditions or in a subpopulation of cells in other bacterial species. It is possible that CRAϕ-like phages restrict horizontal gene transfer in nature by inhibiting the growth of naturally transformable strains. We also found that prophages with homology to CRAϕ exist in several strains ofAcinetobacter baumannii. These CRAϕ-likeA. baumanniiprophages encode toxins similar to CTXϕ that might contribute to the virulence of this opportunistic multidrug-resistant pathogen.IMPORTANCEWe observed the emergence of a novel filamentous phage (CRAϕ) from the genome ofAcinetobacter baylyiADP1 during a long-term laboratory evolution experiment. CRAϕ is the first bacteriophage reported to require the molecular machinery involved in the uptake of environmental DNA for infection. Reactivation and evolution of CRAϕ reduced the potential for horizontal transfer of genes via natural transformation in our experiment. Risk of infection by similar phages may limit the expression and maintenance of bacterial competence in nature. The closest studied relative of CRAϕ is theVibrio choleraeCTXϕ phage. Variants of CRAϕ are found in the genomes ofAcinetobacter baumanniistrains, and it is possible that phage-encoded toxins contribute to the virulence of this opportunistic multidrug-resistant pathogen.

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Graupner, Stefan, and Wilfried Wackernagel. "Pseudomonas stutzeri Has Two Closely RelatedpilA Genes (Type IV Pilus Structural Protein) with Opposite Influences on Natural Genetic Transformation." Journal of Bacteriology 183, no. 7 (April 1, 2001): 2359–66. http://dx.doi.org/10.1128/jb.183.7.2359-2366.2001.

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ABSTRACT Pseudomonas stutzeri has type IV pili for which the pilA gene (here termed pilAI) provides the structural protein and which are required for DNA uptake and natural genetic transformation. Downstream of pilAIwe identified a gene, termed pilAII, coding for a deduced protein with a size similar to that of PilAI with 55% amino acid sequence identity and with a typical leader peptide including a leader peptidase cleavage site. Fusions to lacZ revealed that pilAII is expressed only about 10% compared topilAI, although the genes are cotranscribed as shown by reverse transcription-PCR. Surprisingly, insertional inactivation ofpilAII produced a hypertransformation phenotype giving about 16-fold-increased transformation frequencies. Hypertransformation also occurred in pilAI pilAII double mutants expressing heterologous pilA genes of nontransformable bacteria, like Pseudomonas aeruginosa or Dichelobacter nodosus. The overexpression of pilAII decreased transformation up to 5,000-fold compared to that of thepilAII mutant. However, neither inactivation ofpilAII nor its overexpression affected the amounts of [3H]thymidine-labeled DNA that were competence-specifically bound and taken up by the cells. In thepilAII mutant, the transformation by purified single-stranded DNA (which depends on comA andexbB, as does transformation by duplex DNA) was also increased 17-fold. It is concluded that PilAII suppresses a step in transformation after the uptake of duplex DNA into the cell and perhaps before its translocation into the cytoplasm. The idea that the degree of the transformability of cells could be permanently adjusted by the expression level of an antagonistic protein is discussed.

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Rodgers, Katherine, Cindy Grove Arvidson, and Stephen Melville. "Expression of a Clostridium perfringens Type IV Pilin by Neisseria gonorrhoeae Mediates Adherence to Muscle Cells." Infection and Immunity 79, no. 8 (June 6, 2011): 3096–105. http://dx.doi.org/10.1128/iai.00909-10.

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ABSTRACTClostridium perfringensis an anaerobic, Gram-positive bacterium that causes a range of diseases in humans, including lethal gas gangrene. We have recently shown that strains ofC. perfringensmove across the surface of agar plates by a unique type IV pilus (TFP)-mediated social motility that had not been previously described. Based on sequence homology to pilins in Gram-negative bacteria,C. perfringensappears to have two pilin subunits, PilA1 and PilA2. Structural prediction analysis indicated PilA1 is similar to the pseudopilin found inKlebsiella oxytoca, while PilA2 is more similar to true pilins found in the Gram-negative pathogensPseudomonas aeruginosaandNeisseria gonorrhoeae. Strains ofN. gonorrhoeaethat were genetically deficient in the native pilin, PilE, but supplemented with inducible expression of PilA1 and PilA2 ofC. perfringenswere constructed. Genetic competence, wild-type twitching motility, and attachment to human urogenital epithelial cells were not restored by expression of either pilin. However, attachment to mouse and rat myoblast (muscle) cell lines was observed with theN. gonorrhoeaestrain expressing PilA2. Significantly, wild-typeC. perfringenscells adhered to mouse myoblasts under anaerobic conditions, and adherence was 10-fold lower in apilTmutant that lacked functional TFP. These findings implicateC. perfringensTFP in the ability ofC. perfringensto adhere to and move along muscle fibersin vivo, which may provide a therapeutic approach to limiting this rapidly spreading and highly lethal infection.

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Duggan, Paula S., Priscila Gottardello, and David G. Adams. "Molecular Analysis of Genes in Nostoc punctiforme Involved in Pilus Biogenesis and Plant Infection." Journal of Bacteriology 189, no. 12 (April 6, 2007): 4547–51. http://dx.doi.org/10.1128/jb.01927-06.

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ABSTRACT Hormogonia are the infective agents in many cyanobacterium-plant symbioses. Pilus-like appendages are expressed on the hormogonium surface, and mutations in pil-like genes altered surface piliation and reduced symbiotic competency. This is the first molecular evidence that pilus biogenesis in a filamentous cyanobacterium requires a type IV pilus system.

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ANDERSONE, U. "Changes of Morphogenic Competence in Mature Pinus sylvestris L. Buds in vitro." Annals of Botany 90, no. 2 (August 1, 2002): 293–98. http://dx.doi.org/10.1093/aob/mcf176.

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Gayatri, Maria. "Determinants of IUD Use in Sukmajaya Sub District, Depok: A Qualitative Research." Jurnal Kesehatan Komunitas 5, no. 3 (December 31, 2019): 185–90. http://dx.doi.org/10.25311/keskom.vol5.iss3.467.

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A qualitative research through Rapid Assessment Procedure on the Behavior of Intrauterine Device (IUD) use was carried out in Sukmajaya District, Depok. The aims of this research ware to analyxe predisposing, enabling and reinforcing factors influencing the use of IUDs. The informants were mother who use IUD, mother who ever use IUD and mother who use non-IUD methods (such as pills and injectables). The results showed that the informants understood IUD effective methods to prevent pregnancy. Most informants considered that IUDs were cheap, available at health facilities and the service given by competence providers. Support from husband, encouragement from friends who successfully used the IUD and the effectivity and reversibility of IUDs were also as strength factors for IUDs use. However, there were some factors that inhibit the use of IUDs such as side effects, rumors of IUDs, incomplete counseling from providers and sharing negative experiences of friend who have failed to use IUD. In conclusion, IUD used was influenced by multi-factors such as predisposing factors (knowledge, values, beliefs, attitude of perception), enabling factors (access to information, availability of IUDs, officer competencies, regulations) and reinforcing factors (husband, friends, health workers).

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Berger, Bernhard. "Kritische Gedanken zur Revision von Art. 7 IPRG im Lichte eines praktischen Beispiels." ASA Bulletin 29, Issue 1 (March 1, 2011): 33–44. http://dx.doi.org/10.54648/asab2011005.

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Since 20 March 2008, a Parliamentary Initiative is pending before the Swiss Parliament which aims at amending Article 7 of the PILS in the sense that Switzerland would accede to the theory of the so-called "negative effect" of competence-competence. In the ASA Bulletin vol. 3/2010 at pp. 478-485, Pierre-Yves Tschanz recently presented his views on the advisability to vote in favor of the proposed amendment ('De l'opportunité de modifier l'art. 7 LDIP'). The author of the present article considers that a recent case decided by the Swiss Federal Supreme Court (BGer 4A_279/2010) gives rise to some critical reflections on the proposal to amend Article 7 of the PILS. Besides a number of legal reservations, the author is not convinced that, as opposed to what the text of the Initiative promises, importing the "negative effect" of competence-competence into Swiss law would boost and further promote Switzerland as a major place for international arbitration. In addition, he believes that it is doubtful whether the proposed amendment would be in the best interests of the Swiss economy. While reducing the risk of parallel proceedings before arbitral tribunals and state courts is a concern that deserves to be supported, the author suggests that the proposed amendment to Article 7 of the PILS does not appear to be the appropriate way to proceed in this matter. Instead of going for a "national solo", it would be much wiser to concentrate the Swiss recourses on helping to develop uniform transnational standards in relation to potential conflicts between arbitral and state court jurisdiction. As a first step, for example, the UNCITRAL could and should prepare a Recommendation regarding the interpretation of Article II(3) of the New York Convention (as it exists for Article II(2) since 2006). By all means, Switzerland should refrain from taking further action in this matter until such time as it is clear how the EU intends to proceed with the "arbitration exception" in the ongoing revision of Brussels I.

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Ellis, David D., and D. E. Bilderback. "TEMPORAL COMPETENCE OF EMBRYONIC PINUS PONDEROSA COTYLEDONS TO FORM MULTIPLE BUDS IN VITRO." American Journal of Botany 76, no. 3 (March 1989): 348–55. http://dx.doi.org/10.1002/j.1537-2197.1989.tb11321.x.

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Raffle, V. L., N. A. Anderson, G. R. Furnier, and R. L. Doudrick. "Variation in mating competence and random amplified polymorphic DNA inLaccaria bicolor(Agaricales) associated with three tree host species." Canadian Journal of Botany 73, no. 6 (June 1, 1995): 884–90. http://dx.doi.org/10.1139/b95-096.

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We examined the population genetic structure of the ectomycorrhizal fungus Laccaria bicolor (Maire) Orton using single spore homokaryotic cultures from 33 basidiomes collected in northern Minnesota in association with red pine (Pinus resinosa Ait.), jack pine (Pinus banksiana Lamb.), and trembling aspen (Populus tremuloides Michx.) of three age-classes (0–20 years, 21–40 years, and > 41 years). Mating competence between cultures of isolates, as determined by the presence of clamp connections, revealed the presence of two subpopulations that were not freely interbreeding, one composed of 29 dikaryons, the other of 3 dikaryons. Phenetic cluster analysis using random amplified polymorphic DNA markers did not reveal differentiation between these subpopulations. Clustering failed to reveal genetically distinct groups based on incompatibility group, tree host species, or geographic origin of isolates. Key words: heterogenic incompatibility, RAPD, population genetics.

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Abnisa, Almaydza Pratama, and Zubairi Zubairi. "Personality Competence Educator and Students Interest in Learning." Scaffolding: Jurnal Pendidikan Islam dan Multikulturalisme 4, no. 1 (March 5, 2022): 279–90. http://dx.doi.org/10.37680/scaffolding.v4i1.1289.

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The purpose of this research is to find the relevance of the personality competence of educators with students' interest in learning. The method used in this study is the library method, where the researcher collects data based on library sources relevant to the research. The study results are that the personality competence of Islamic religious education teachers is an essential part of the learning process for students because the educator's personality is all the attitudes and actions of a teacher who shows good traits and personalities that can affect the achievement of learning objectives. As for the personal competence of teachers in the learning process, among others; Be pious and have faith in Allah SWT, believe in yourself, be wise and tolerant, be open and democratic, be patient in carrying out the teaching profession, develop yourself for professional progress, understand the purpose of education, be able to establish relationships between humans, understand your strengths and weaknesses, Be creative and innovative in the workplace. So, a good personality possessed by educators will also have a good impact on increasing student interest in learning, in other words, the better the personality competence of PAI teachers, the better interest in student learning will be.

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Sahid, Juwanita. "Enkulturasi Nilai-Nilai “Keislaman” dalam Proses Pembelajaran di TK Wihdatul Ummah Kota Makassar." Emik 3, no. 1 (June 30, 2020): 80–102. http://dx.doi.org/10.46918/emik.v3i1.494.

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Early childhood education (PAUD) is a social institution that serves to instill cultural, national, and religious values in children. While the existing literatures on PAUD are more focused on the role of social institutions and formal educational institutions in the formation of children (school environment, learning process and community supporting the process), this article focuses on the process of enculturation in applying "Islamic" values in the learning process at TK Wihdatul Ummah. This study was conducted at TK Wihdatul Ummah. Using ethnographic approach, data was collcted using in-depth interview ansd observation. The study involved ten informants who are varied on the basis of age (between 27 and 69 years), and status, consisting of a school principals, three teachers, five parents and a student’ guardian. The study shows that TK Wihdatul Ummah has succeeded in carrying out Wahdah Islamiyah's main mission in the field of education, mainly in developing young generation from an early age by fostering faith (aqidah), monotheism (tauhid), faith (iman) and good deeds (amal sholeh). Character building based on "Islamic" values is the main orientation that is encultured by TK Wihdatul Ummah to early childhood and still refers to the PAUD National Curriculum. TK Wihdatul Ummah has been able to transmit an "Islamic" curriculum that focuses on two core competencies, namely to love the Qur'an and the Hadith and practice Islamic values as the character of pious children. Achievement of competence to love the Qur'an and the Hadith is shown in basic competency activities, namely: memorizing the surahs in juz 30 and reciting the Hadiths of the Prophet, taddabur Al-Qur'an and Hadith, studying hijaiyyah letters, and knowing practical worship according to the guidance of the Prophet. While the attainment of the “Islamic” values as the character of pious children, is shown by Islamic behaviour in daily life, and Islamic independent behavior. Students’ learning achievements at TK Wihdatul Ummah include discipline, independence and self-confidence; trust and closeness to the teacher; able to socialize; able to appreciate and understand others; able to understand rewards and punishment; and able to practice Islamic values as sholeh children character. From the emic point of view based on emic perspective (teachers and parents), the achievement in terms of children character building at TK Wihdatul Ummah focuses on religious values (praying independently and according to guidance, worshiping and remembrancing) and morals values (getting used to behaving well, polite, honest, like to give/help and respect) and social emotional values (independence, self-confidence able to socialize, respect and understand others, control themselves naturally, understand the rules and discipline). By studying at TK Wihdatul Ummah, it is not only students, but also parents show significant changes in their everyday behaviour.

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Cortizo, Millán, Candela Cuesta, María Luz Centeno, Ana Rodríguez, Belén Fernández, and Ricardo Ordás. "Benzyladenine metabolism and temporal competence of Pinus pinea cotyledons to form buds in vitro." Journal of Plant Physiology 166, no. 10 (July 2009): 1069–76. http://dx.doi.org/10.1016/j.jplph.2008.12.013.

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Cambrón-Sandoval, Víctor Hugo, Humberto Suzán-Azpiri, Cuauhtémoc Sáenz-Romero C., and Naúm Sánchez-Vargas. "Desarrollo de Pinus pseudostrobus bajo distintos ambientes de crecimiento en jardín común." Madera y Bosques 20, no. 1 (April 30, 2014): 47–57. http://dx.doi.org/10.21829/myb.2014.201175.

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A partir de un análisis de componentes principales (ACP), se plantea la interpretación y clasificación de tres ambientes de competencia sobre el desarrollo de individuos de P. pseudostrobus integrando resultados previamente publicados dentro del mismo ensayo; las variables evaluadas fueron: el crecimiento (altura y diámetro a la base del tallo), producción de clorofila (cantidad de pigmentos de clorofila a y b), supervivencia, producción y distribución de biomasa total, raíz, rama, hoja y tallo, y arquitectura de crecimiento (largo de rama y altura de inserción de la primera rama) en familias de medios hermanos de P. pseudostrobus evaluados en un ensayo de jardín común a 10 meses de edad bajo tres ambientes de competencia. (I) baja densidad inter-familiar (0.24 × 0.12 m), (II) alta densidad inter-familiar (0.12 × 0.06 m) y (III) alta densidad intra-familiar (0.12 × 0.06 m). Se estimó que los tres componentes con mayor peso (CP) explican el 82.9% de la variación total. El componente principal de mayor varianza se interpreta como crecimiento (CP1), agrupando a las familias por ambiente de competencia; al aumentar la densidad de plantación, posteriormente, las familias se agrupan por la capacidad de supervivencia y por la plasticidad fisiológica (CP2). Finalmente, la diferencia entre los ambientes la hace la plasticidad fenotípica de las familias como respuesta al ambiente de competencia (cambios en la arquitectura) (CP3). Los resultados evidenciaron un elevado nivel de plasticidad fenotípica de P. pseudostrobus y se hace hincapié en la importancia de la selección de ambientes y de genotipos acordes para aumentar la adaptación y productividad en los programas de mejora.

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Cambrón-Sandoval, Víctor H., Humberto Suzán-Azpiri, J. Jesús Vargas-Hernández, Nahum M. Sánchez-Vargas, and Cuauhtémoc Sáenz-Romero. "ESTRATEGIAS DE CRECIMIENTO Y DISTRIBUCIÓN DE BIOMASA EN Pinus pseudostrobus BAJO DIFERENTES CONDICIONES DE COMPETENCIA." Revista Fitotecnia Mexicana 36, no. 1 (March 15, 2013): 71. http://dx.doi.org/10.35196/rfm.2013.1.71.

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La intensidad de competencia en la que se desarrollan los individuos es un factor importante en la supervivencia, producción de biomasa y estrategia del crecimiento de la planta (arquitectura), características que interaccionan con su genotipo. En el presente estudio se evaluó el efecto de niveles de competencia en 13 familias juveniles de medios hermanos de Pinus pseudostrobus Lindl., sobre su supervivencia, producción y distribución de biomasa. Se compararon las condiciones: (I) baja densidad (0.25 × 0.12 m) con múltiples familias aleatorizadas (inter-familiar), (II) alta densidad (0.12 × 0.06 m) con grupos inter-familiares, y (III) alta densidad (0.12 × 0.06 m) con parcelas monofamiliares (intra-familiar), establecidas en un ensayo de jardín común bajo un diseño de parcelas divididas con cuatro repeticiones y cuatro individuos por familia. A 10 meses de establecido el ensayo se cosecharon dos repeticiones. Se detectaron diferencias entre condiciones de competencia (P ≤ 0.05) para todas las variables evaluadas de producción, distribución de biomasa, supervivencia y arquitectura de crecimiento. A nivel de familia se identificaron estrategias en el crecimiento de los individuos semejantes a los tres comportamientos clásicos de arquetipos (de aislamiento, de competencia y de cultivo), así como genotipos que pudieron ajustar su crecimiento en función del ambiente de competencia. Los resultados obtenidos reflejan la importancia de la selección de ambientes y de genotipos para aumentar su adaptación y productividad en los programas de mejoramiento.

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Savidge, Rodney Arthur. "Coniferin, a biochemical indicator of commitment to tracheid differentiation in conifers." Canadian Journal of Botany 67, no. 9 (September 1, 1989): 2663–68. http://dx.doi.org/10.1139/b89-343.

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Endogenous E-coniferin was characterized chemically and found to accumulate in cambia of Picea glauca, Pinus banksiana, Pinus strobus, and Larix laricina at the time of resumption of springtime cell-division activity and well before the initiation of lignification in differentiating tracheids. Coniferin content, quantified by high performance liquid chromatography, was highest on the centripetal side of the cambium, in developing xylem, at time of radial expansion of cambial derivatives. Stem ringing resulted in coniferin accumulation above the ring and disappearance below the ring. Coniferin was absent from leaves and dormant cambia. Exogenous coniferin was metabolized rapidly by in vitro cultures of P. strobus cambium grown on a defined medium containing the auxins 1-naphthalene acetic acid and indol-3-yl acetic acid and the cytokinin benzylaminopurine. The evidence suggests coniferin content of the cambium will be of practical value for determining commitment to and competence for wood formation in conifers.

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Yoshihara, Shizue, XiaoXing Geng, Shinobu Okamoto, Kei Yura, Takashi Murata, Mitiko Go, Masayuki Ohmori, and Masahiko Ikeuchi. "Mutational Analysis of Genes Involved in Pilus Structure, Motilityand Transformation Competency in the Unicellular Motile CyanobacteriumSynechocystis sp. PCC6803." Plant and Cell Physiology 42, no. 1 (January 15, 2001): 63–73. http://dx.doi.org/10.1093/pcp/pce007.

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Sasmita, Reni, and Mhd Lailan Arqam. "Kompetensi Kepribadian Guru Dalam Perpektif Muhammadiyah." TA'DIBUNA: Jurnal Pendidikan Agama Islam 5, no. 1 (June 21, 2022): 21. http://dx.doi.org/10.30659/jpai.5.1.21-31.

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The problems that occur in Muhammadiyah teachers are their behavior that is less moral, has a bad personality, and also weak mastery of religious norms. So this will have an impact on the professionalism of a teacher. What happened to teachers at Muhammadiyah schools was due to the weak mastery and understanding of the personality competencies that a teacher must-have. The method used in this research is the library method, which is a research method whose data sources come from books, scientific articles, and documents related to the topic of the problem. The conclusion of this study is that not only is the source of knowledge, but a teacher is also a person who is nurtured and imitated by his students. Teachers at Muhammadiyah schools are teachers who not only master the knowledge they teach but also have to master and understand Muhammadiyah and also have piety to God and are able to be role models for their students. The Personality Competence of Muhammadiyah teachers as contained in the Guidelines for the Islamic Life of Muhammadiyah Citizens (PHIWM) which is also in accordance with Law no. 14 of 2005 concerning teachers and lecturers are compassionate, Uswatun Hashanah, noble character (pious personality), Islamic work ethic, and also Istiqomah Commitment. The personality of Muhammadiyah teachers must be reflected in their daily lives, both in the school, family, and community and within the scope of the Muhammadiyah organization.�

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Flinn, Barry S., David T. Webb, and William Newcomb. "The role of cell clusters and promeristemoids in determination and competence for caulogenesis by Pinus strobus cotyledons in vitro." Canadian Journal of Botany 66, no. 8 (August 1, 1988): 1556–65. http://dx.doi.org/10.1139/b88-214.

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Exposure of Pinus strobus cotyledons to a modified Schenk and Hildebrandt medium containing N6-benzyladenine revealed that caulogenic determination was present after 4 days and culminated by day 7. Delaying exposure to N6-benzyladenine by preculture on basal medium for 2 days caused a significant reduction in competence for caulogenesis. Competence declined steadily and explants were incompetent by day 14 of culture. Organized three- and four-celled clusters were present by day 4 in the presence or absence of N6-benzyladenine. The number of cell clusters was enhanced on N6-benzyladenine as a result of an increase of three- and four-celled clusters, plus the development of five- and six-celled clusters. The latter were similar to promeristemoids, and their appearance parallelled increasing levels of caulogenic determination. On growth regulator free basal medium, the number and organization of cell clusters did not change from day 4 to 7. Cell clusters were absent by day 14 on growth regulator free medium, when explants were incompetent to respond caulogenically.

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Fage-Butler, Antoinette Mary. "The Discursive Construction of Risk and Trust in Patient Information Leaﬂets." HERMES - Journal of Language and Communication in Business 24, no. 46 (October 24, 2017): 61. http://dx.doi.org/10.7146/hjlcb.v24i46.97368.

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There is wide recognition that the communication of risk in Patient Information Leaﬂets (PILs) – the instructions that accompany medications in Europe – problematises the reception of these texts. There is at the same time growing understanding of the mediating role of trust in risk communication. This paper aims to analyse how risk is discursively constructed in PILs, and to identify and analyse discourses that are associated with trust-generation. The corpus (nine PILs chosen from the British online PIL bank, www.medicines.org.uk) is analysed using Foucauldian (1972) discourse analysis: speciﬁcally, this involves identifying the functions of the statements that constitute the discourses. A discourse analysis of the corpus of PILs reveals that the discourse of risk revolves around statements of the potential harm that may be caused by taking the medication, whilst trust is constructed through three discourses: the discourses that relate to competence and care, in accordance with the trust theories of Poortinga/Pidgeon (2003) and Earle (2010), and a third discourse, corporate accountability, which functions to construct an ethical (trustworthy) identity for the company. This paper contributes to PIL literature in the following ways: it introduces a methodology that has not been used before in relation to these texts, namely, Foucauldian discourse analysis; it helps to identify the presence of trust-generating discourses in PILs; and analysing the discourses of risk and trust at statement-level facilitates a better understanding of how these discourses function in texts that are generally not well-received by the patients for whom they are intended.

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Journal articles on the topic 'Competence pilus'

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