Bibliografías temáticas / Sporulation

Literatura académica sobre el tema "Sporulation"

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Publicado: 4 de junio de 2021
Última modificación: 6 de septiembre de 2023

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Artículos de revistas sobre el tema "Sporulation"

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Fernández-García, Gemma, Nathaly González-Quiñónez, Beatriz Rioseras, Sergio Alonso-Fernández, Javier Fernández, Felipe Lombó y Ángel Manteca. "The SCO2102 Protein Harbouring a DnaA II Protein-Interaction Domain Is Essential for the SCO2103 Methylenetetrahydrofolate Reductase Positioning at Streptomyces Sporulating Hyphae, Enhancing DNA Replication during Sporulation". International Journal of Molecular Sciences 23, n.º 9 (30 de abril de 2022): 4984. http://dx.doi.org/10.3390/ijms23094984.

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Streptomyces DNA replication starts with the DnaA binding to the origin of replication. Differently to most bacteria, cytokinesis only occurs during sporulation. Cytokinesis is modulated by the divisome, an orderly succession of proteins initiated by FtsZ. Here, we characterised SCO2102, a protein harbouring a DnaA II protein–protein interaction domain highly conserved in Streptomyces. The ΔSCO2102 knockout shows highly delayed sporulation. SCO2102-mCherry frequently co-localises with FtsZ-eGFP during sporulation and greatly reduces FtsZ-eGFP Z-ladder formation, suggesting a role of SCO2102 in sporulation. SCO2102 localises up-stream of SCO2103, a methylenetetrahydrofolate reductase involved in methionine and dTMP synthesis. SCO2102/SCO2103 expression is highly regulated, involving two promoters and a conditional transcription terminator. The ΔSCO2103 knockout shows reduced DNA synthesis and a non-sporulating phenotype. SCO2102-mCherry co-localises with SCO2103-eGFP during sporulation, and SCO2102 is essential for the SCO2103 positioning at sporulating hyphae, since SCO2103-eGFP fluorescent spots are absent in the ΔSCO2102 knockout. We propose a model in which SCO2102 positions SCO2103 in sporulating hyphae, facilitating nucleotide biosynthesis for chromosomal replication. To the best of our knowledge, SCO2102 is the first protein harbouring a DnaA II domain specifically found during sporulation, whereas SCO2103 is the first methylenetetrahydrofolate reductase found to be essential for Streptomyces sporulation.
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2

Ferreira, Julio C., Anita D. Panek y Pedro S. de Araujo. "Inactivation of maltose permease and maltase in sporulatingSaccharomyces cerevisiae". Canadian Journal of Microbiology 46, n.º 4 (1 de abril de 2000): 383–86. http://dx.doi.org/10.1139/w99-136.

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Maltose transport and maltase activities were inactivated during sporulation of a MAL constitutive yeast strain harboring different MAL loci. Both activities were reduced to almost zero after 5 h of incubation in sporulation medium. The inactivation of maltase and maltose permease seems to be related to optimal sporulation conditions such as a suitable supply of oxygen and cell concentration in the sporulating cultures, and occurs in the fully derepressed conditions of incubation in the sporulation acetate medium. The inactivation of maltase and maltose permease under sporulation conditions in MAL constitutive strains suggests an alternative mechanism for the regulation of the MAL gene expression during the sporulation process.Key words: maltase activity, maltose permease activity, sporulation, Saccharomyces cerevisiae.
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3

Edwards, Adrianne N., Kathryn L. Nawrocki y Shonna M. McBride. "Conserved Oligopeptide Permeases Modulate Sporulation Initiation in Clostridium difficile". Infection and Immunity 82, n.º 10 (28 de julio de 2014): 4276–91. http://dx.doi.org/10.1128/iai.02323-14.

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ABSTRACTThe anaerobic gastrointestinal pathogenClostridium difficilemust form a metabolically dormant spore to survive in oxygenic environments and be transmitted from host to host. The regulatory factors by whichC. difficileinitiates and controls the early stages of sporulation inC. difficileare not highly conserved in otherClostridiumorBacillusspecies. Here, we investigated the role of two conserved oligopeptide permeases, Opp and App, in the regulation of sporulation inC. difficile. These permeases are known to positively affect sporulation inBacillusspecies through the import of sporulation-specific quorum-sensing peptides. In contrast to other spore-forming bacteria, we discovered that inactivating these permeases inC. difficileresulted in the earlier expression of early sporulation genes and increased sporulationin vitro. Furthermore, disruption ofoppandappresulted in greater virulence and increased the amounts of spores recovered from feces in the hamster model ofC. difficileinfection. Our data suggest that Opp and App indirectly inhibit sporulation, likely through the activities of the transcriptional regulator SinR and its inhibitor, SinI. Taken together, these results indicate that the Opp and App transporters serve a different function in controlling sporulation and virulence inC. difficilethan inBacillus subtilisand suggest that nutrient availability plays a significant role in pathogenesis and sporulationin vivo. This study suggests a link between the nutritional status of the environment and sporulation initiation inC. difficile.
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4

Hao, Jiang y Kathleen E. Kendrick. "Visualization of Penicillin-Binding Proteins during Sporulation of Streptomyces griseus". Journal of Bacteriology 180, n.º 8 (15 de abril de 1998): 2125–32. http://dx.doi.org/10.1128/jb.180.8.2125-2132.1998.

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ABSTRACT We used fluorescein-tagged β-lactam antibiotics to visualize penicillin-binding proteins (PBPs) in sporulating cultures ofStreptomyces griseus. Six PBPs were identified in membranes prepared from growing and sporulating cultures. The binding activity of an 85-kDa PBP increased fourfold by 10 to 12 h of sporulation, at which time the sporulation septa were formed. Cefoxitin inhibited the interaction of the fluorescein-tagged antibiotics with the 85-kDa PBP and also prevented septum formation during sporulation but not during vegetative growth. The 85-kDa PBP, which was the predominant PBP in membranes of cells that were undergoing septation, preferentially bound fluorescein-6-aminopenicillanic acid (Flu-APA). Fluorescence microscopy showed that the sporulation septa were specifically labeled by Flu-APA; this interaction was blocked by prior exposure of the cells to cefoxitin at a concentration that interfered with septation. We hypothesize that the 85-kDa PBP is involved in septum formation during sporulation of S. griseus.
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Perez, Ana R., Angelica Abanes-De Mello y Kit Pogliano. "Suppression of Engulfment Defects in Bacillus subtilis by Elevated Expression of the Motility Regulon". Journal of Bacteriology 188, n.º 3 (1 de febrero de 2006): 1159–64. http://dx.doi.org/10.1128/jb.188.3.1159-1164.2006.

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ABSTRACT During Bacillus subtilis sporulation, the transient engulfment defect of spoIIB strains is enhanced by spoVG null mutations and suppressed by spoVS null mutations. These mutations have opposite effects on expression of the motility regulon, as the spoVG mutation reduces and the spoVS mutation increases σD-directed gene expression, cell separation, and autolysis. Elevating σD activity by eliminating the anti-σ factor FlgM also suppresses spoIIB spoVG, and both flgM and spoVS mutations cause continued expression of the σD regulon during sporulation. We propose that peptidoglycan hydrolases induced during motility can substitute for sporulation-specific hydrolases during engulfment. We find that sporulating cells are heterogeneous in their expression of the motility regulon, which could result in phenotypic variation between individual sporulating cells.
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6

Ozsarac, N., M. J. Straffon, H. E. Dalton y I. W. Dawes. "Regulation of gene expression during meiosis in Saccharomyces cerevisiae: SPR3 is controlled by both ABFI and a new sporulation control element." Molecular and Cellular Biology 17, n.º 3 (marzo de 1997): 1152–59. http://dx.doi.org/10.1128/mcb.17.3.1152.

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The SPR3 gene encodes a sporulation-specific homolog of the yeast Cdc3/10/11/12 family of bud neck filament proteins. It is expressed specifically during meiosis and sporulation in Saccharomyces cerevisiae. Analysis of the sporulation-specific regulation of SPR3 has shown that it is strongly activated under sporulating conditions but shows low levels of expression under nonsporulating conditions. A palindromic sequence located near the TATA box is essential to the developmental regulation of this gene and is the only element directly activating SPR3 at the right time during sporulation. Within the palindrome is a 9-bp sequence, gNCRCAAA(A/T) (midsporulation element [MSE]), found in the known control regions of three other sporulation genes. A previously identified ABFI element is also needed for activation. The MSE has been shown to activate a heterologous promoter (CYC1) in a sporulation-specific manner. Related sequences, including an association of MSE and ABFI elements, have been found upstream of other genes activated during the middle stage of S. cerevisiae sporulation. One group of these may be involved in spore coat formation or maturation.
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de JONG, A. E. I., R. R. BEUMER y F. M. ROMBOUTS. "Optimizing Sporulation of Clostridium perfringens". Journal of Food Protection 65, n.º 9 (1 de septiembre de 2002): 1457–62. http://dx.doi.org/10.4315/0362-028x-65.9.1457.

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Many sporulation media have been developed for Clostridium perfringens, but none stimulates sporulation for all strains. The aim of our experiments was to develop a sporulation method using Duncan and Strong (DS) medium, which supports sporulation of a wide variety of strains. Different inoculation levels were tested, and the effects of sporulation-promoting substances and acid shock were evaluated. Furthermore, DS medium was compared with other sporulation media. Highest spore numbers in DS medium were obtained with a 10% 24-h fluid thioglycollate broth inoculum (5.0 × 105/ml). Addition of theophylline and replacement of starch by raffinose increased spore yields for some strains, but most strains were not affected (average increases in log N/ml of 0.2 and 0.3, respectively). One strain was enhanced by the addition of bile, but other strains were strongly inhibited (average decrease in log N/ml of 2.5); agar did not influence sporulation. Neither short-time acid exposure nor addition of culture supernatant fluids of well-sporulating strains resulted in higher spore numbers in DS medium. None of the tested methods enhanced sporulation in general; only strain-dependent effects were obtained. Peptone bile theophylline medium was the most promising sporulation medium tested; peptone bile theophylline starch medium yielded highest spore numbers (2.5 × 105/ml), but some strains failed to sporulate. In conclusion, adding theophylline to DS medium may optimize sporulation of C. perfringens, but peptone bile theophylline medium with or without starch is most suitable.
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8

Adler, Elliot, Imrich Barák y Patrick Stragier. "Bacillus subtilis Locus Encoding a Killer Protein and Its Antidote". Journal of Bacteriology 183, n.º 12 (15 de junio de 2001): 3574–81. http://dx.doi.org/10.1128/jb.183.12.3574-3581.2001.

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ABSTRACT We have isolated mutations that block sporulation after formation of the polar septum in Bacillus subtilis. These mutations were mapped to the two genes of a new locus, spoIIS. Inactivation of the second gene,spoIISB, decreases sporulation efficiency by 4 orders of magnitude. Inactivation of the first gene, spoIISA, has no effect on sporulation but it fully restores sporulation of aspoIISB null mutant, indicating that SpoIISB is required only to counteract the negative effect of SpoIISA on sporulation. An internal promoter ensures the synthesis of an excess of SpoIISB over SpoIISA during exponential growth and sporulation. In the absence of SpoIISB, the sporulating cells show lethal damage of their envelope shortly after asymmetric septation, a defect that can be corrected by synthesizing SpoIISB only in the mother cell. However, forced synthesis of SpoIISA in exponentially growing cells or in the forespore leads to the same type of morphological damage and to cell death. In both cases protection against the killing effect of SpoIISA can be provided by simultaneous synthesis of SpoIISB. The spoIIS locus is unique to B. subtilis, and since it is completely dispensable for sporulation its physiological role remains elusive.
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9

Silvaggi, Jessica M., David L. Popham, Adam Driks, Patrick Eichenberger y Richard Losick. "Unmasking Novel Sporulation Genes in Bacillus subtilis". Journal of Bacteriology 186, n.º 23 (1 de diciembre de 2004): 8089–95. http://dx.doi.org/10.1128/jb.186.23.8089-8095.2004.

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ABSTRACT The Bacillus subtilis transcription factor σE directs the expression of a regulon of 262 genes, but null mutations in only a small fraction of these genes severely impair sporulation. We have previously reported that mutations in seven σE-controlled genes cause a mild (2- to 10-fold) defect in sporulation. In this study, we found that pairwise combinations of some of these seven mutations led to strong synthetic sporulation phenotypes, especially those involving the ytrHI operon and ybaN. Double mutants of ybaN and ytrH and of ybaN and ytrI had >10,000-fold lower sporulation efficiencies than the wild type. Thin-section electron microscopy revealed a block in cortex formation for the ybaN ytrH double mutant and coat defects for the ybaN single and ybaN ytrI double mutants. Sporulating cells of a ybaN ytrI double mutant and of a ybaN ytrHI triple mutant exhibited a pronounced loss of dipicolinic acid (DPA) between hours 8 and 24 of sporulation, in contrast to the constant levels seen for the wild type. An analysis of the spore cortex peptidoglycans of the ybaN ytrI and ybaN ytrHI mutants showed striking decreases in the levels of total muramic acid by hour 24 of sporulation. These data, along with the loss of DPA in the mutants, suggest that the developing spores were unstable and that the cortex underwent degradation late in sporulation. The existence of otherwise hidden sporulation pathways indicates that functional redundancy may mask the role of hitherto unrecognized sporulation genes.
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Eswaramoorthy, Prahathees, Daniel Duan, Jeffrey Dinh, Ashlee Dravis, Seram Nganbiton Devi y Masaya Fujita. "The Threshold Level of the Sensor Histidine Kinase KinA Governs Entry into Sporulation in Bacillus subtilis". Journal of Bacteriology 192, n.º 15 (28 de mayo de 2010): 3870–82. http://dx.doi.org/10.1128/jb.00466-10.

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ABSTRACT Sporulation in Bacillus subtilis is controlled by a complex gene regulatory circuit that is activated upon nutrient deprivation. The initial process is directed by the phosphorelay, involving the major sporulation histidine kinase (KinA) and two additional phosphotransferases (Spo0F and Spo0B), that activates the master transcription factor Spo0A. Little is known about the initial event and mechanisms that trigger sporulation. Using a strain in which the synthesis of KinA is under the control of an IPTG (isopropyl-β-d-thiogalactopyranoside)-inducible promoter, here we demonstrate that inducing the synthesis of the KinA beyond a certain level leads to the entry of the irreversible process of sporulation irrespective of nutrient availability. Moreover, the engineered cells expressing KinA under a σH-dependent promoter that is similar to but stronger than the endogenous kinA promoter induce sporulation during growth. These cells, which we designated COS (constitutive sporulation) cells, exhibit the morphology and properties of sporulating cells and express sporulation marker genes under nutrient-rich conditions. Thus, we created an engineered strain displaying two cell cycles (growth and sporulation) integrated into one cycle irrespective of culture conditions, while in the wild type, the appropriate cell fate decision is made depending on nutrient availability. These results suggest that the threshold level of the major sporulation kinase acts as a molecular switch to determine cell fate and may rule out the possibility that the activity of KinA is regulated in response to the unknown signal(s).
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Tesis sobre el tema "Sporulation"

1

com, rohanlowe@gmail y Rohan George Thomas Lowe. "Sporulation of Stagonospra nodorum". Murdoch University, 2006. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20071101.221432.

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Stagonospora nodorum is a necrotrophic fungal pathogen that is the causal agent of leaf and glume blotch on wheat. Very little is currently known about the molecular mechanisms required for pathogenicity of S. nodorum, despite its major impact on Australian agriculture. S. nodorum is a polycyclic pathogen. Rain-splashed pycnidiospores attach to and colonise wheat tissue and subsequently sporulate within 2-3 weeks. Several cycles of infection are needed to build up inoculum for the damaging infection of flag leaves and heads, sporulation is therefore a critical component of the infection cycle of S. nodorum; our aim is to determine the genetic and biochemical requirements for sporulation for development of control of the pathogen. Disease progression of S. nodorum on wheat cv. Amery was monitored by light microscopy to determine the time point when pycnidia development began. Early pycnidia development was evident 12 days post-infection. This information was used to guide a genomics and a metabolomics based approach to determine the requirements for sporulation in S. nodorum. The genomics approach utilised two cDNA libraries created from sporulating and non-sporulating cultures. EST frequency was used to determine highly expressed genes under the two developmental states. Gene expression from the most highly represented genes during sporulation were confirmed using quantitative PCR. A gene encoding an arabitol 4-dehydrogenase (Abd1), was mutagenised, in its absence sporulation was reduced by approximately 20%. The metabolomics approach isolated metabolites from both in planta infection and in vitro growth. Rapid changes in the abundance of metabolites were detected during the onset of sporulation. Key fungal metabolites identified include mannitol and trehalose. The concentration of both mannitol and trehalose increased dramatically in concert with pycnidia formation. Both mannitol and trehalose have also been linked to pathogenicity in filamentous fungi. Creation of deletion mutants of the gene encoding trehalose 6-phosphate synthase showed the synthesis of trehalose is required for full sporulation of S. nodorum in planta and in vitro.
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Lowe, Rohan George Thomas. "Sporulation of Stagonospora nodorum /". Access via Murdoch University Digital Theses Project, 2006. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20071101.221432.

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Lowe, Rohan George Thomas. "Sporulation of Stagonospra nodorum". Thesis, Lowe, Rohan George Thomas (2006) Sporulation of Stagonospra nodorum. PhD thesis, Murdoch University, 2006. https://researchrepository.murdoch.edu.au/id/eprint/166/.

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Stagonospora nodorum is a necrotrophic fungal pathogen that is the causal agent of leaf and glume blotch on wheat. Very little is currently known about the molecular mechanisms required for pathogenicity of S. nodorum, despite its major impact on Australian agriculture. S. nodorum is a polycyclic pathogen. Rain-splashed pycnidiospores attach to and colonise wheat tissue and subsequently sporulate within 2-3 weeks. Several cycles of infection are needed to build up inoculum for the damaging infection of flag leaves and heads, sporulation is therefore a critical component of the infection cycle of S. nodorum; our aim is to determine the genetic and biochemical requirements for sporulation for development of control of the pathogen. Disease progression of S. nodorum on wheat cv. Amery was monitored by light microscopy to determine the time point when pycnidia development began. Early pycnidia development was evident 12 days post-infection. This information was used to guide a genomics and a metabolomics based approach to determine the requirements for sporulation in S. nodorum. The genomics approach utilised two cDNA libraries created from sporulating and non-sporulating cultures. EST frequency was used to determine highly expressed genes under the two developmental states. Gene expression from the most highly represented genes during sporulation were confirmed using quantitative PCR. A gene encoding an arabitol 4-dehydrogenase (Abd1), was mutagenised, in its absence sporulation was reduced by approximately 20%. The metabolomics approach isolated metabolites from both in planta infection and in vitro growth. Rapid changes in the abundance of metabolites were detected during the onset of sporulation. Key fungal metabolites identified include mannitol and trehalose. The concentration of both mannitol and trehalose increased dramatically in concert with pycnidia formation. Both mannitol and trehalose have also been linked to pathogenicity in filamentous fungi. Creation of deletion mutants of the gene encoding trehalose 6-phosphate synthase showed the synthesis of trehalose is required for full sporulation of S. nodorum in planta and in vitro.
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Lowe, Rohan George Thomas. "Sporulation of Stagonospra nodorum". Lowe, Rohan George Thomas (2006) Sporulation of Stagonospra nodorum. PhD thesis, Murdoch University, 2006. http://researchrepository.murdoch.edu.au/166/.

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Stagonospora nodorum is a necrotrophic fungal pathogen that is the causal agent of leaf and glume blotch on wheat. Very little is currently known about the molecular mechanisms required for pathogenicity of S. nodorum, despite its major impact on Australian agriculture. S. nodorum is a polycyclic pathogen. Rain-splashed pycnidiospores attach to and colonise wheat tissue and subsequently sporulate within 2-3 weeks. Several cycles of infection are needed to build up inoculum for the damaging infection of flag leaves and heads, sporulation is therefore a critical component of the infection cycle of S. nodorum; our aim is to determine the genetic and biochemical requirements for sporulation for development of control of the pathogen. Disease progression of S. nodorum on wheat cv. Amery was monitored by light microscopy to determine the time point when pycnidia development began. Early pycnidia development was evident 12 days post-infection. This information was used to guide a genomics and a metabolomics based approach to determine the requirements for sporulation in S. nodorum. The genomics approach utilised two cDNA libraries created from sporulating and non-sporulating cultures. EST frequency was used to determine highly expressed genes under the two developmental states. Gene expression from the most highly represented genes during sporulation were confirmed using quantitative PCR. A gene encoding an arabitol 4-dehydrogenase (Abd1), was mutagenised, in its absence sporulation was reduced by approximately 20%. The metabolomics approach isolated metabolites from both in planta infection and in vitro growth. Rapid changes in the abundance of metabolites were detected during the onset of sporulation. Key fungal metabolites identified include mannitol and trehalose. The concentration of both mannitol and trehalose increased dramatically in concert with pycnidia formation. Both mannitol and trehalose have also been linked to pathogenicity in filamentous fungi. Creation of deletion mutants of the gene encoding trehalose 6-phosphate synthase showed the synthesis of trehalose is required for full sporulation of S. nodorum in planta and in vitro.
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Underwood, Sarah. "Sporulation initiation in Clostridium difficile". Thesis, University of Leeds, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.505066.

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Clostridium difficile is a leading cause of hospital-acquired diarrhoea, responsible for over 30% of cases of antibiotic-associated colitis, nearly all cases of pseudomembranous colitis and costs the NHS over œ200 million per year. This bacterium is able to persist in the hospital environment to cause recurrent infection by the formation of stable spores, refractile to current decontamination procedures. A more comprehensive understanding of the sporulation signal transduction pathway is essential for the design of a decontamination regime effective in removing the spores from the nosocomial environment and the logical design of novel antimicrobial agents. This project aimed to elucidate the mechanism of sporulation initiation . regulation and the role of sporulation-associated proteins in other C. difficile virulence processes, such as toxin production and colonisation. Analysis of sporulation in response to various hospital cleaning agents showed that the combination of a neutral detergent (such as Hospec) with EDTA is a more effective cleaning agent than the chlorine-based agents currently used, as the combination product is uniquely able to both kill vegetative cells and inhibit spore formation. A variety of molecular approaches were used to elucidate information regarding the C. difficile sporulation initiation pathway and the relationship between sporulation and toxin production. Three putative C. difficile sporulation-associated sensor histidine kinases (CD1A, CD2A and CD3B) were identified and shown to be independently involved in sporulation initiation. Furthermore, CD3B has been shown to directly phosphorylate the master response regulator SpoOA, strongly suggesting that this pathway is a two-component system, as opposed to the extended phosphore lay pathway found in B. subtilis. Previous studies on bacteria capable of both toxin production and endospore formation have described links between the two processes. Data presented here indicates SpoOA has a role in indirectly regulating C. difficile toxin A and B production, as the protein is capable of specifically binding promoter regions of the toxin regulatory genes tcdC and tcdD. Inoculation of a triple-stage continuous-culture chemostat that modelled the human gut with C. difficile spoDA- mutant provided further evidence that SpoDA has a key role in both colonisation a!1d toxin production. Overall, this work adds to the growing body of evidence that SpaDA is a master global regulator and has a crucial role in the pathogenicity of C. difficile, making it an excellent target for future novel antimicrobial therapies.
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6

Cardaman, Richard C. "Sporulation mutants of Myxococcus xanthus". Case Western Reserve University School of Graduate Studies / OhioLINK, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=case1057779064.

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Polak, Eline. "Asexual sporulation in the basidiomycete Coprinus cinereus /". [S.l.] : [s.n.], 1999. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=13125.

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Davidson, Philip. "Evolutionary Remodeling of the Sporulation Initiation Pathway". Research Showcase @ CMU, 2017. http://repository.cmu.edu/dissertations/1026.

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Signal transduction pathways allow organisms to sense and respond appropriately to a complex bouquet of environmental cues. The molecular determinants of specificity are constrained by the demands of signaling fidelity, yet flexible enough to allow pathway remodeling to meet novel environmental challenges. A detailed picture of how these forces shape bacterial two-component signaling systems has emerged over the last decade. However, the tension between constraint and flexibility in more complex architectures has not been well-studied. In this thesis, I combine comparative genomics and in vitro phosphotransfer experiments to investigate pathway remodeling using the Firmicutes sporulation initiation (Spo0) pathway as a model. The present-day Spo0 pathways in Bacilli and Clostridia share common ancestry, but possess different architectures. In Clostridia, a sensor kinase phosphorylates Spo0A, the master regulator of the sporulation, directly. In Bacilli, Spo0 is phosphorylated/activated indirectly via a four-protein phosphorelay. The presence in sister lineages of signaling pathways that activate the same response regulator and control analogous phenotypes, yet possess with different architectures, suggests a common ancestral pathway that evolved through interaction remodeling. The prevailing theory is that the ancestral pathway was a simpler, direct phosphorylation architecture; the more complex phosphorelay emerged within the Bacillar lineage. In contrast to this prevailing view, my analysis of 84 representative genomes supports a novel hypothesis for the evolution of Spo0 architectures, wherein the two protein, direct phosphorylation architecture is a derived state, which arose from an ancestral Spo0 phosphorelay. The combination of my bioinformatic analysis and the first experimental characterization of a Clostridial phosphorelay provide evidence for the presence of functional phosphorelays in both classes Bacilli and Clostridia. Further, a cross-species complementation assay between phosphorelays from each class suggests that interaction specificity has been conserved since the divergence of this phylum, 2.7 BYA. My results reveal a patchy phylogenetic distribution of both Spo0 pathway architectures, consistent with repeated remodeling events, in which a phosphorelay was replaced with a two protein, direct phosphorylation pathway. This remodeling likely occurred via acquisition of a sensor kinase with direct specificity for Spo0A. Further, my analysis suggests that the unusual architectures of the Spo0 pathway and its striking tendency to gain and lose interactions may be due to the juxtaposition of three key properties: the maintenance of interaction specificity through molecular recognition; the ecological role of endosporulation; and the degeneracy of interaction space that permits the ongoing recruitment of kinases to recognize novel environmental signals.
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Anco, Daniel J. "Epidemiological Studies of the Sporulation Potential and Environmental Factors Affecting Sporulation of Phomopsis viticola on Infected Grapevines". The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1322495236.

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Arab, Najafi Seyed Mahmoud. "Control of compartment-specific sigma (#sigma'F) in Bacillus subtilis". Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318858.

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Libros sobre el tema "Sporulation"

1

Sykes, David. The growth and sporulation of Verticillium chlamydosporium. Manchester: University of Manchester, 1994.

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2

Pleurotus unter Stress: Ökophysiologische Untersuchungen zu Wasserhaushalt und Sporulation. Berlin: J. Cramer, 1992.

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Ebisuzaki, Lawrence Kentaro. Promoter analysis of the sporulation-specific gene SPS4 of the yeast Saccharomyces cerevisiae. Ottawa: National Library of Canada = Bibliothèque nationale du Canada, 1993.

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4

Issar, Smith, Slepecky Ralph, Setlow Peter y International Spore Conference (10th : 1988 : Woods Hole, Mass.), eds. Regulation of procaryotic development: Structural and functional analysis of bacterial sporulation and germination. Washington, D.C: American Society for Microbiology, 1989.

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Issar, Smith, Slepecky Ralph, Setlow Peter y International Spore Conference, (10th : 1988 : Woods Hole, Mass.), eds. Regulation of procaryotic development: A structural and functional analysis of bacterial sporulation and germination. Washington, D.C: American Society for Microbiology, 1989.

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Molnár, Enikö. Role of Rim 101 in mitotic repression of the yeast sporulation-specific genes DIT1 and DIT2. Ottawa: National Library of Canada, 2001.

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Tanny, Jason Chaim. Functional analysis of NREDIT, an element that controls expression of mid-late sporulation-specific genes in Saccharomyces cervisiae. Ottawa: National Library of Canada, 1998.

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Garg, G. K. Final technical report (Jan. 1982 to Dec. 1986) on studies on factors influencing sporulation, dipicolinic acid synthesis and heat resistance in bacterial spores to obtain information for improving methods of preservation of food products. Pantnagar, U.P., India: Department of Biochemistry, College of Basic Sciences & Humanities, G.B. Pant University of Agriculture & Technology, 1986.

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Kurtz, Stephen E. Analysis of gene expression during sporulation in yeast. 1985.

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Rahn-Lee, Lilah Lillian. The Control of DNA Replication During Sporulation in Bacillus subtilis. 2010.

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Capítulos de libros sobre el tema "Sporulation"

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Horneck, Gerda. "Sporulation". En Encyclopedia of Astrobiology, 1567. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-11274-4_1496.

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Horneck, Gerda. "Sporulation". En Encyclopedia of Astrobiology, 2333–34. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-662-44185-5_1496.

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Spencer, John F. T., Dorothy M. Spencer y I. J. Bruce. "Sporulation". En Yeast Genetics, 8–15. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-73356-7_3.

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Gooch, Jan W. "Sporulation". En Encyclopedic Dictionary of Polymers, 925. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-6247-8_14854.

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Horneck, Gerda. "Sporulation". En Encyclopedia of Astrobiology, 1. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-27833-4_1496-3.

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Horneck, Gerda. "Sporulation". En Encyclopedia of Astrobiology, 2837. Berlin, Heidelberg: Springer Berlin Heidelberg, 2023. http://dx.doi.org/10.1007/978-3-662-65093-6_1496.

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Li, Jihong, Daniel Paredes-Sabja, Mahfuzur R. Sarker y Bruce A. McClane. "Clostridium perfringens Sporulation and Sporulation-Associated Toxin Production". En The Bacterial Spore, 331–47. Washington, DC, USA: ASM Press, 2016. http://dx.doi.org/10.1128/9781555819323.ch16.

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Doi, Roy H. "Sporulation and Germination". En Bacillus, 169–215. Boston, MA: Springer US, 1989. http://dx.doi.org/10.1007/978-1-4899-3502-1_8.

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Bärlocher, Felix. "Sporulation by Aquatic Hyphomycetes". En Methods to Study Litter Decomposition, 241–45. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-30515-4_26.

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Beakes, G. W. "Sporulation of Lower Fungi". En The Growing Fungus, 339–66. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-0-585-27576-5_16.

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Actas de conferencias sobre el tema "Sporulation"

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Safiullin, R. T. y E. I. Chalysheva. "CULTURE OF EIMERIA SPP. OOCYSTS OF TURKEY POULTS AND THEIR SPECIES IDENTIFICATION". En THEORY AND PRACTICE OF PARASITIC DISEASE CONTROL. All-Russian Scientific Research Institute for Fundamental and Applied Parasitology of Animals and Plant – a branch of the Federal State Budget Scientific Institution “Federal Scientific Centre VIEV”, 2023. http://dx.doi.org/10.31016/978-5-6048555-6-0.2023.24.414-419.

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In our country, in recent years, much attention has been paid to the development of poultry meat production, especially turkey breeding. In the conditions of industrial turkey breeding, when a large number of poultry is kept in a limited area, there is a high risk of parasitic diseases, one of which is eimeriosis. Knowledge of the species composition of Eimeria on a particular poultry farm is of great practical importance for the reasonable development of effective methods to control invasion and to monitor Eimeria resistance to the drugs used. Eimeria species were identified after the end of sporulation. To assess the course of sporulation of Eimeria oocysts during their cultivation, at least 500 oocysts were examined from each Petri dish every six hours under a high magnification microscope (x400) paying special attention to their morphology. When examining and studying litter samples 24 hours after they were put on cultivation, sporulated Eimeria oocysts of turkeys were detected in all six dishes in 37.8% to 60.6% of those examined, and the average rate was 51.6%. At 48 hours after the start of cultivation, the average Eimeria sporulation rate was 83.4%. The results of species identification of Eimeria oocysts showed that the following Eimeria species were found in young turkeys on the poultry farm of the Tula Region: Eimeria meleagrimitis (60.0%), E. gallopavonis (25.0%), E. meleagridis (10.0%), and E. adenoides (5.0%).
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Morimoto, Michael, Adam Arkin y Kameshwar Poolla. "Modeling sporulation decisions in Bacillus subtilis as optimal evolutionary decision-making". En 2011 American Control Conference. IEEE, 2011. http://dx.doi.org/10.1109/acc.2011.5991554.

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Raychaudhuri, Soumya, Joshua M. Stuart y Russ B. Altman. "PRINCIPAL COMPONENTS ANALYSIS TO SUMMARIZE MICROARRAY EXPERIMENTS: APPLICATION TO SPORULATION TIME SERIES". En Proceedings of the Pacific Symposium. WORLD SCIENTIFIC, 1999. http://dx.doi.org/10.1142/9789814447331_0043.

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Marwan, Wolfgang. "A Systems Genetics Approach to the Sporulation Control Network in Physarum polycephalum". En 9th EAI International Conference on Bio-inspired Information and Communications Technologies (formerly BIONETICS). ACM, 2016. http://dx.doi.org/10.4108/eai.3-12-2015.2262394.

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Singh, Swarnjeet y Anu Kalia. "Assessing the effect of nanoparticles on hyphal growth and sporulation in Ganoderma lucidum". En Proceedings of the International Conference on Nanotechnology for Better Living. Singapore: Research Publishing Services, 2016. http://dx.doi.org/10.3850/978-981-09-7519-7nbl16-rps-300.

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Zhang, Dongsheng, Zheng Wang y Wei Zhou. "Effect of Ca2+, Mg2+, Mn2+ on Growth and Sporulation of Bacillus sp. L15". En 2018 7th International Conference on Energy, Environment and Sustainable Development (ICEESD 2018). Paris, France: Atlantis Press, 2018. http://dx.doi.org/10.2991/iceesd-18.2018.74.

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Astapchuk, I. L., N. A. Marchenko, G. V. Yakuba y A. I. Nasonov. "Selection of the optimal culture medium for cultivation Fusarium sporotrichioides Sherb". En CURRENT STATE, PROBLEMS AND PROSPECTS OF THE DEVELOPMENT OF AGRARIAN SCIENCE. Federal State Budget Scientific Institution “Research Institute of Agriculture of Crimea”, 2020. http://dx.doi.org/10.33952/2542-0720-2020--5-9-10-3.

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The influence of various culture media on the growth, morphological and cultural characteristics of the fungus F. sporotrichioides was studied. Ten culture media were used in our research. A comparative study of the growth rate of the F. sporotrichioides mycelium made it possible to identify two media that are the most suitable for the cultivation and identification of this species, namely carrot and tomato agar. We took into account such criteria as ensuring the maximum degree of sporulation, rapid growth and development of mycelium (the 7th day), colony diameter (71–78 mm), as well as the ease of preparation. Nirenberg culture medium can be used to obtain a large number of conidia of the fungus. Because of the high variability of cultural characteristics of F. sporotrichioides, we recommend using different composition of media.
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Perera, TVRC, K. Pakeerathan y A. Nirosha. "ECO-FRIENDLY MANAGEMENT COMMON LAB CONTAMINANT Trichoderma spp IN OYSTER MUSHROOM PRODUCTION USING AGROBASED INDUSTRY’S BY-PRODUCTS". En The 5th International Conference on Climate Change 2021 – (ICCC 2021). The International Institute of Knowledge Management, 2021. http://dx.doi.org/10.17501/2513258x.2021.5105.

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An abundant supply of low-cost substrate and management of green mold disease-causing fungus Trichoderma are the major hurdles in successful mushroom production. This study aimed to identify the best Agro-based industry’s by-products as a substitute for oyster mushroom production (Pleurotus ostreatus) while managing fungal contaminants eco-friendly. Two sets of In-Vitro [containing 20% extracts, from agro-based industries, such as coffee waste powder, tea dust and Mahua oil cake] and In-Vivo experiments [four substrates such as paddy straw, wood sawdust, paddy husk and banana leaves were incorporated with coffee powder, tea dust and Mahua oil cake] were prepared separately. All the experiments were conducted using a complete randomized design with three replicates. The In-Vitro data [mycelial growth and sporulation of both fungi], In-Vivo data [mycelial mushroom run, pinhead formation and yield] were subjected to ANOVA and DMRT mean separation using SAS 9.1 statistical package at P <0.05. In-Vitro results showed that the Trichoderma mycelial growth was significantly minimum in Mahua (2.5 cM) and coffee (3.6 cM) in comparison to control, whereas, with decreasing concentration of coffee, tea, and Mahua extract P. ostreatus showed enhanced growth. Trichoderma sporulation had significantly affected coffee treatment, and even not sporulate in Mahua treated plants. The In-Vivo experiment proved that spawn run was consistent and significant among the treatments when mixed tea (20 days) and coffee (21 days), respectively, at P <0.05. Treatment wise coffee treated spawn bags took an average of 32.5 days, whereas, in tea-treated substrates, it was more than 36 days to form pinhead. Mahua treated trials showed poor spawn run in all substrates, longer days of pinhead formation, and lower yield. In contrast, the paddy straw + coffee treatment produced a significantly highest yield of 200.67g. When sawdust was the substrate, the addition of tea showed a significantly higher yield of 185.00g than coffee (145.00g). In conclusion, coffee and tea extracts have a significant effect on yield with paddy straw and sawdust while minimizing the growth of Trichoderma. Keywords: Pleurotus ostreatus, eco-friendly, plant extract, substrate, coffee, paddy straw
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Gonzalez, Andrés, Harold Castro, Mario Villamizar, Nicolás Cuervo, Gabriel Lozano, Silvia Restrepo y Sergio Orduz. "Mesoscale Modeling of the Bacillus Thuringiensis Sporulation Network Based on Stochastic Kinetics and Its Application for in Silico Scale-Down". En 2009 International Workshop on High Performance Computational Systems Biology (HIBI). IEEE, 2009. http://dx.doi.org/10.1109/hibi.2009.17.

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Mikityuk, O. D., T. M. Voinova, N. V. Statsyuk y V. G. Dzhavakhiya. "Suppression of sporulation, pigmentation and zearalenone production in Fusarium culmorum by 6-demethylmevinolin, an inhibitor of the aflatoxin B1 biosynthesis". En ACTUAL PROBLEMS OF ORGANIC CHEMISTRY AND BIOTECHNOLOGY (OCBT2020): Proceedings of the International Scientific Conference. AIP Publishing, 2022. http://dx.doi.org/10.1063/5.0069162.

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Informes sobre el tema "Sporulation"

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Sanabria, Johana, Ginna Quiroga, Cindy Mejía, Erika Grijalba y Martha Goméz. Effect of abiotic factors on viability and characterization of Metarhizium rileyi Nm017. Corporación colombiana de investigación agropecuaria - AGROSAVIA, 2019. http://dx.doi.org/10.21930/agrosavia.poster.2019.18.

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The species Chloridea virescens and Helicoverpa zea (Lepidoptera: Noctuidae) are declared agricultural pests with a high economic impact worldwide (Angulo et al. 2008). They are widely distributed on the American continent, and agrochemical are the most common method to control, which can cause environmental, social, economic and public impacts. A strain of Metarhizium rileyi Nm017 [AGROSAVIA - Orinoquia area (Col.)], demonstrated an e cacy of 75.8% on C. virescens, and 92.5% on H. zea on laboratory conditions. Mass production and virulence of Metarhizium sp. are susceptible to stress conditions such as temperature, UVB radiation and pH, a ecting conidial vigor, germination, and sporulation (Rangel et al. 2008, Oliveira et al. 2016). Likewise, the culture medium can a ect the infection processes measured through hydrophobicity and enzymatic activities (Ortiz 2013). The identi cation of these parameters allows selecting the most favorable conditions for its production and the challenges that must be assumed in downstream processes.
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Israel, Alvaro y John Merrill. Production of Seed Stocks for Sustainable Tank Cultivation of the Red Edible Seaweed Porphyra. United States Department of Agriculture, 2006. http://dx.doi.org/10.32747/2006.7696527.bard.

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Porphyra species (commonly known as ‘nori’ or ‘purple laver’) are edible red seaweeds rich in proteins, vitamins and other highly valued biogenic compounds. For years Porphyra has been cultured using seeded nets extended in the open sea, and its biomass consumed primarily in the Far East. While demands for international markets have increased steadily at an average of 20% per year, supplies are on the verge and not expected to meet future demands. Alternatively, land-based cultivation of seaweed has become attractive in the mariculture industry since (1) important growth parameters can be controlled, (2) is environmentally friendly and (3) perfectly matches with integrated aquaculture leading to sustainable, high quality products. During the last few years a tank cultivation technology for Porphyra has been developed at the Israeli institution. This technology is based on indoor production of asexual spores and their subsequent growth to 1-2 mm seedlings. The seedlings are then transferred to outdoor tanks and ponds when seawater temperatures drop to 20 °C, or below, and days become shorter during winter time. However, the current technology efficiently serves only about 100 m2 of ponds during one growth season. In order to produce seedlings in sufficient amounts, it is critical to address both technical and biological aspects of seedling production, securing optimal up-scale to commercial-size cultivation farms. We hypothesize that massive production of spores is related to thalli origin, thalli age and sporulation triggers, and that seedling survival and their subsequent growth potential is determined by the seawater quality and overall indoor growth conditions imposed. A series of bio-reactors were constructed and tested in which spore release and spore growth were separately studied. The main assessment criteria for optimal viability of the seedlings will be by determining their electron transport rate using PAM fluorometry and by subsequent growth and biomass yields in outdoor ponds. Altogether the project showed (1), controlled sporulation is possible in big outdoor/growth chamber settings provided initial stock material (small frozen seedlings) is at hand, (2), contamination problems can be almost completely avoided if stock material is properly handled (clean as possible and partially dehydrated prior to freezing), (3), spore release can significantly be enhance using high nutrient levels during thawing for P. yezoensis and P. haitanensis, but not for P. rosengurttii, (4), PAM fluorometry is an efficient tool to estimate growth capacity in both seedlings and juvenile thalli. The BARD funding also served to explore other aspects of Porphyra biology and cultivation. For example, the taxonomical status of Porphyra strains used in this study was defined (see appendix), and the potential use of this seaweed in bioremediation was well substantiated. In addition, BARD funding supported a number of opportunities and activities in the Israeli lab, direct or indirectly related to the initial objectives of the project such as: additional molecular work in other seaweeds, description of at least 2 new species for the Israeli Mediterranean, and continuous support for the writing of a book on Global Change and applied aspects of seaweeds. The technology for Porphyra cultivation in land-based ponds is readily available. This study corroborated previous know-how of Porphyra growth in tanks and ponds, and yet offers important improvements regarding seedling production and their handling for successful cultivation. This study supported various other activities opening additional important issues in the biology/cultivation/use of Porphyra and other seaweeds.
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Droby, Samir, Tim R. Gottwald, Richard Stange, Efraim Lewinsohn y T. Gregory McCollum. Characterization of the biochemical basis of host specificity of Penicillium digitatum and Penicillium italicum on citrus fruit. United States Department of Agriculture, mayo de 2008. http://dx.doi.org/10.32747/2008.7587726.bard.

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l. This research demonstrates that citrus fruit volatiles play an important role in host recognition by P. digitatum and P. italicum. 2. Volatiles derived from non-host fruits and vegetables (apple, pear, tomato, pepper, strawberry and avocado) had no effect on promotion of spore germination and growth of citrus pathogens. 3. Citrus volatiles have a specific stimulatory effect solely on P. digitatum and P. italicum. Non-citrus pathogens such as P. expansum and B. cinerea not affected orinhibited by the volatile materials. The specific stimulatory effect of fruit peelvolatiles on citrus pathogens and inhibitory effect on non-pathogens indicateimport ant role of volatile compounds in the host selectivity of citrus postharvestpathogens. 4. Comparative CG-MS quantification was per formed and identification of volatileconstituents of citrus commercial oils, peel extracts and the headspace of thewounded fruits was completed. Monoterpenehydrocarbons (limonene, a-pinene,sabinene, and myrcene) were the most abundant in all volatiles regardless of thesource. 5. Our results demonstrated stimulation of germination and germ tube growth in both P. digitatum and P. italicum by limonene, myrcene, a-pinene, and b-pinene). Limonenewas show n to be the most efficient in induction of germination and growth in bothpathogens. 6. P. digitatum spores placed on the surface of lemon fruit, adjacent to a wounded oil gland, were induced to germinate and grow, thus supporting all the in vitro results and demonstrating that the phenomenon of stimulation of germination and growth occurs on the fruit. 7. We established that P. digitatum is capable of biotransformation of limonene to a terpineol. a-terpinel was proved to be involved in induction of fungal sporulation process. 8. Chemotropism (directional growth) of P. digitatum towards the volatiles released from the oil glands on fruit surface was demonstrated. 9. Citrus germplasm screening work for fruit susceptibility/resistance for P. digitatum infection showed no definitive results regarding host range and susceptibility.Although the sour orange selections appear to show higher resistance to infection and decay development. 10. We demonstrated that P. expansum, non citrus pathogen, is capable of germinating in citrus fruit surface wounds, but it strongly induced host resistance mechanisms which restrict it growth and prevented decay development. The host (citrus fruit) reacted strongly by production of ROS. On the other hand, P. digitatum seems to actively suppress host natural resistance mechanisms possibly through inhibiting the production of ROS production.
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Lichter, Amnon, Joseph L. Smilanick, Dennis A. Margosan y Susan Lurie. Ethanol for postharvest decay control of table grapes: application and mode of action. United States Department of Agriculture, julio de 2005. http://dx.doi.org/10.32747/2005.7587217.bard.

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Original objectives: Dipping of table grapes in ethanol was determined to be an effective measure to control postharvest gray mold infection caused by Botrytis cinerea. Our objectives were to study the effects of ethanol on B.cinerea and table grapes and to conduct research that will facilitate the implementation of this treatment. Background: Botrytis cinerea is known as the major pathogen of table grapes in cold storage. To date, the only commercial technology to control it relied on sulfur dioxide (SO₂) implemented by either fumigation of storage facilities or from slow release generator pads which are positioned directly over the fruits. This treatment is very effective but it has several drawbacks such as aftertaste, bleaching and hypersensitivity to humans which took it out of the GRAS list of compounds and warranted further seek for alternatives. Prior to this research ethanol was shown to control several pathogens in different commodities including table grapes and B. cinerea. Hence it seemed to be a simple and promising technology which could offer a true alternative for storage of table grapes. Further research was however required to answer some practical and theoretical questions which remained unanswered. Major conclusions, solutions, achievements: In this research project we have shown convincingly that 30% ethanol is sufficient to prevent germination of B. cinerea and kill the spores. In a comparative study it was shown that Alternaria alternata is also rather sensitive but Rhizopus stolonifer and Aspergillus niger are less sensitive to ethanol. Consequently, ethanol protected the grapes from decay but did not have a significant effect on occurrence of mycotoxigenic Aspergillus species which are present on the surface of the berry. B. cinerea responded to ethanol or heat treatments by inducing sporulation and transient expression of the heat shock protein HSP104. Similar responses were not detected in grape berries. It was also shown that application of ethanol to berries did not induce subsequent resistance and actually the berries were slightly more susceptible to infection. The heat dose required to kill the spores was determined and it was proven that a combination of heat and ethanol allowed reduction of both the ethanol and heat dose. Ethanol and heat did not reduce the amount or appearance of the wax layers which are an essential component of the external protection of the berry. The ethanol and acetaldehyde content increased after treatment and during storage but the content was much lower than the natural ethanol content in other fruits. The efficacy of ethanol applied before harvest was similar to that of the biological control agent, Metschnikowia fructicola, Finally, the performance of ethanol could be improved synergistically by packaging the bunches in modified atmosphere films which prevent the accumulation of free water. Implications, both scientific and agricultural: It was shown that the major mode of action of ethanol is mediated by its lethal effect on fungal inoculum. Because ethanol acts mainly on the cell membranes, it was possible to enhance its effect by lowering the concentration and elevating the temperature of the treatment. Another important development was the continuous protection of the treated bunches by modified atmosphere that can solve the problem of secondary or internal infection. From the practical standpoint, a variety of means were offered to enhance the effect of the treatment and to offer a viable alternative to SO2 which could be instantly adopted by the industry with a special benefit to growers of organic grapes.
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