Journal articles: 'Bac7'

1

Armas, Federica, Adriana Di Stasi, Mario Mardirossian, Antonello A. Romani, Monica Benincasa, and Marco Scocchi. "Effects of Lipidation on a Proline-Rich Antibacterial Peptide." International Journal of Molecular Sciences 22, no. 15 (July 26, 2021): 7959. http://dx.doi.org/10.3390/ijms22157959.

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The emergence of multidrug-resistant bacteria is a worldwide health problem. Antimicrobial peptides have been recognized as potential alternatives to conventional antibiotics, but still require optimization. The proline-rich antimicrobial peptide Bac7(1-16) is active against only a limited number of Gram-negative bacteria. It kills bacteria by inhibiting protein synthesis after its internalization, which is mainly supported by the bacterial transporter SbmA. In this study, we tested two different lipidated forms of Bac7(1-16) with the aim of extending its activity against those bacterial species that lack SbmA. We linked a C12-alkyl chain or an ultrashort cationic lipopeptide Lp-I to the C-terminus of Bac7(1-16). Both the lipidated Bac-C12 and Bac-Lp-I forms acquired activity at low micromolar MIC values against several Gram-positive and Gram-negative bacteria. Moreover, unlike Bac7(1-16), Bac-C12, and Bac-Lp-I did not select resistant mutants in E. coli after 14 times of exposure to sub-MIC concentrations of the respective peptide. We demonstrated that the extended spectrum of activity and absence of de novo resistance are likely related to the acquired capability of the peptides to permeabilize cell membranes. These results indicate that C-terminal lipidation of a short proline-rich peptide profoundly alters its function and mode of action and provides useful insights into the design of novel broad-spectrum antibacterial agents.

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Zanetti, M., L. Litteri, R. Gennaro, H. Horstmann, and D. Romeo. "Bactenecins, defense polypeptides of bovine neutrophils, are generated from precursor molecules stored in the large granules." Journal of Cell Biology 111, no. 4 (October 1, 1990): 1363–71. http://dx.doi.org/10.1083/jcb.111.4.1363.

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Bactenecins are highly cationic polypeptides of bovine neutrophil granules and exert in vitro a potent antimicrobial activity. We have previously purified two bactenecins, designated in an abbreviated form Bac7 and Bac5 from their approximate molecular masses of 7 and 5 kD (Gennaro, R., B. Skerlavaj, and D. Romeo. 1989. Infect. Immun. 57:3142-3146). Here we have studied the biosynthesis, processing, and localization of precursors of Bac7 and Bac5 in bovine bone marrow cells of the myeloid lineage. In vitro translation directed by mRNA isolated from these cells has shown that the primary translation products are preprobactenecins of 23.5 and 21 kD, and are processed to polypeptides of 20 and 15.8 kD, respectively. The 20-kD polypeptide is the granule storage form of Bac7, or proBac7, as also demonstrated by Western blot analysis of lysates of peripheral neutrophils. Between 15 and 50 min from the beginning of its biosynthesis the 15.8-kD polypeptide is converted into the 15-kD granule storage form of Bac5, or proBac5. As shown by immunogold EM, proBac7 and proBac5 are sorted and targeted to the matrix of the so called large granules, which are the predominant organelles in the cytoplasm of bovine neutrophils and are the exclusive store of the nonoxidative antimicrobial system of these cells. Solubilization of granules with Triton X-100 with concomitant unmasking of proteases leads to cleavage of the proforms to Bac7 and Bac5. Experiments performed with protease inhibitors suggest that the proteolytic cleavage is catalyzed in detergent-solubilized neutrophils by neutral serine protease(s), very likely derived from the azurophil granules.

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Marlow, Victoria L., Andreas F. Haag, Hajime Kobayashi, Vivien Fletcher, Marco Scocchi, Graham C. Walker, and Gail P. Ferguson. "Essential Role for the BacA Protein in the Uptake of a Truncated Eukaryotic Peptide in Sinorhizobium meliloti." Journal of Bacteriology 191, no. 5 (December 12, 2008): 1519–27. http://dx.doi.org/10.1128/jb.01661-08.

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ABSTRACT The inner membrane BacA protein is essential for the establishment of chronic intracellular infections by Sinorhizobium meliloti and Brucella abortus within plant and mammalian hosts, respectively. In their free-living state, S. meliloti and B. abortus mutants lacking BacA have reductions in their outer membrane lipid A very-long-chain fatty acid (VLCFA) contents and exhibit low-level resistance to the glycopeptide bleomycin in comparison to their respective parent strains. In this paper we investigate the hypothesis that BacA is involved in peptide uptake in S. meliloti. We determined that an S. meliloti ΔbacA mutant is completely resistant to a truncated form of the eukaryotic peptide Bac7, Bac7(1-16), and this phenotype appears to be independent of its lipid A alteration. Subsequently, we discovered that BacA and/or Escherichia coli SbmA is essential for fluorescently labeled Bac7(1-16) uptake in S. meliloti. Given that there are hundreds of root nodule-specific peptides within the legume host, our data suggest that BacA-mediated peptide uptake could play a central role in the chronic infection process of S. meliloti. However, since we determined that two symbiotically defective S. meliloti bacA site-directed mutants (with the Q193G and R389G mutations, respectively) with known reductions in their lipid A VLCFA contents are still capable of peptide uptake, these findings suggest that BacA-dependent peptide uptake cannot fully account for the essential role of BacA in the legume symbiosis. Further, they provide evidence that the BacA function that leads to the S. meliloti lipid A VLCFA modification plays a key role in the chronic infection of legumes.

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Sola, Riccardo, Mario Mardirossian, Bertrand Beckert, Laura Sanghez De Luna, Dennis Prickett, Alessandro Tossi, Daniel N. Wilson, and Marco Scocchi. "Characterization of Cetacean Proline-Rich Antimicrobial Peptides Displaying Activity against ESKAPE Pathogens." International Journal of Molecular Sciences 21, no. 19 (October 6, 2020): 7367. http://dx.doi.org/10.3390/ijms21197367.

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Proline-rich antimicrobial peptides (PrAMPs) may be a valuable weapon against multi-drug resistant pathogens, combining potent antimicrobial activity with low cytotoxicity. We have identified novel PrAMPs from five cetacean species (cePrAMPs), and characterized their potency, mechanism of action and in vitro cytotoxicity. Despite the homology between the N-terminal of cePrAMPs and the bovine PrAMP Bac7, some differences emerged in their sequence, activity spectrum and mode of action. CePrAMPs with the highest similarity with the Bac7(1-35) fragment inhibited bacterial protein synthesis without membrane permeabilization, while a second subgroup of cePrAMPs was more membrane-active but less efficient at inhibiting bacterial translation. Such differences may be ascribable to differences in presence and positioning of Trp residues and of a conserved motif seemingly required for translation inhibition. Unlike Bac7(1-35), which requires the peptide transporter SbmA for its uptake, the activity of cePrAMPs was mostly independent of SbmA, regardless of their mechanism of action. Two peptides displayed a promisingly broad spectrum of activity, with minimal inhibiting concentration MIC ≤ 4 µM against several bacteria of the ESKAPE group, including Pseudomonas aeruginosa and Enterococcus faecium. Our approach has led us to discover several new peptides; correlating their sequences and mechanism of action will provide useful insights for designing optimized future peptide-based antibiotics.

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5

Tomasinsig, Linda, Marco Scocchi, Romina Mettulio, and Margherita Zanetti. "Genome-Wide Transcriptional Profiling of the Escherichia coli Response to a Proline-Rich Antimicrobial Peptide." Antimicrobial Agents and Chemotherapy 48, no. 9 (September 2004): 3260–67. http://dx.doi.org/10.1128/aac.48.9.3260-3267.2004.

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ABSTRACT Most antimicrobial peptides (AMPs) impair the viability of target bacteria by permeabilizing bacterial membranes. However, the proline-rich AMPs have been shown to kill susceptible organisms without causing significant membrane perturbation and may act by inhibiting the activity of bacterial targets. To gain initial insight into the events that follow interaction of a proline-rich peptide with bacterial cells, we used DNA macroarray technology to monitor transcriptional alterations of Escherichia coli in response to challenge with a subinhibitory concentration of the proline-rich Bac7(1-35). Substantial changes in the expression levels of 70 bacterial genes from various functional categories were detected. Among these, 26 genes showed decreased expression, while 44 genes, including genes that are potentially involved in bacterial resistance to antimicrobials, showed increased expression. The generation of a transcriptional response under the experimental conditions used is consistent with the ability of Bac7(1-35) to interact with bacterial components and affect biological processes in this organism.

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6

Benincasa, Monica, Marco Scocchi, Elena Podda, Barbara Skerlavaj, Lucilla Dolzani, and Renato Gennaro. "Antimicrobial activity of Bac7 fragments against drug-resistant clinical isolates." Peptides 25, no. 12 (December 2004): 2055–61. http://dx.doi.org/10.1016/j.peptides.2004.08.004.

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7

Podda, Elena, Monica Benincasa, Sabrina Pacor, Fulvio Micali, Maura Mattiuzzo, Renato Gennaro, and Marco Scocchi. "Dual mode of action of Bac7, a proline-rich antibacterial peptide." Biochimica et Biophysica Acta (BBA) - General Subjects 1760, no. 11 (November 2006): 1732–40. http://dx.doi.org/10.1016/j.bbagen.2006.09.006.

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8

Krizsan, Andor, Daniel Knappe, and Ralf Hoffmann. "Influence of theyjiL-mdtMGene Cluster on the Antibacterial Activity of Proline-Rich Antimicrobial Peptides Overcoming Escherichia coli Resistance Induced by the Missing SbmA Transporter System." Antimicrobial Agents and Chemotherapy 59, no. 10 (July 13, 2015): 5992–98. http://dx.doi.org/10.1128/aac.01307-15.

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ABSTRACTIn view of increasing health threats from multiresistant pathogens, antimicrobial peptides (AMPs) and, specifically, proline-rich AMPs (PrAMPs) have been investigated in animal models. PrAMPs enter bacteria via the ABC transporter SbmA and inhibit intracellular targets. We used phage transduction (Tn10insertion) to screen by random mutagenesis for alternative uptake mechanisms for analogs of apidaecin 1b, a honeybee-derived PrAMP. All 24 apidaecin-resistant mutants had the Tn10insertion in thesbmAgene. ThesesbmA::Tn10insertion mutants and theEscherichia coliBW25113 ΔsbmA(JW0368) strain were still susceptible to the bactenecin PrAMP Bac7(1-35) and oncocin PrAMPs Onc18 and Onc112, as well as to Chex1-Arg20, despite significantly reduced internalizations. In a second round of random mutagenesis, the remaining susceptibility was linked to theyjiL-mdtMgene cluster.E. coliBW25113 and its ΔyjiLnull mutant (JW5785) were equally susceptible to all PrAMPs tested, whereas the BW25113 ΔmdtMmutant was less susceptible to oncocins. The JW0368yjiL::Tn10transposon mutant (BS2) was resistant to all short PrAMPs and susceptible only to full-length Bac7 and A3-APO. Interestingly, PrAMPs appear to enter bacteria via MdtM, a multidrug resistance transporter (drug/H+antiporter) of the major facilitator superfamily (MFS) that can efflux antibiotics, biocides, and bile salts. In conclusion, PrAMPs enter bacteria via ABC and MFS transporters that efflux antibiotics and cytotoxic compounds from the cytoplasm to the periplasm.

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9

Donati, Manuela, Antonietta Di Francesco, Maria Di Paolo, Natascia Fiani, Monica Benincasa, Renato Gennaro, Paola Nardini, Claudio Foschi, and Roberto Cevenini. "Activity of Cathelicidin Peptides against Simkania negevensis." International Journal of Peptides 2011 (April 5, 2011): 1–3. http://dx.doi.org/10.1155/2011/708710.

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The in vitro activity of six cathelicidin peptides against the reference strain Z of Simkania negevensis was investigated. Five peptides—PG-1, Bac7, SMAP-29, BMAP-27, and BMAP-28—proved to be active at very low concentrations (1 to 0.1 μg/mL), while LL-37 cathelicidin was ineffective even at a concentration of 100 μg/mL. In comparison to chlamydiae, S. negevensis proved to be more susceptible to the antimicrobial peptides tested.

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10

Zahn, Michael, Bjorn Kieslich, Nicole Berthold, Daniel Knappe, Ralf Hoffmann, and Norbert Strater. "Structural Identification of DnaK Binding Sites within Bovine and Sheep Bactenecin Bac7." Protein & Peptide Letters 21, no. 4 (February 2014): 407–12. http://dx.doi.org/10.2174/09298665113206660111.

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11

Scocchi, Marco, Domenico Romeo, and Margherita Zanetti. "Molecular cloning of Bac7, a proline- and arginine-rich antimicrobial peptide from bovine neutrophils." FEBS Letters 352, no. 2 (September 26, 1994): 197–200. http://dx.doi.org/10.1016/0014-5793(94)00954-6.

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12

Zanetti, M., L. Litteri, G. Griffiths, R. Gennaro, and D. Romeo. "Stimulus-induced maturation of probactenecins, precursors of neutrophil antimicrobial polypeptides." Journal of Immunology 146, no. 12 (June 15, 1991): 4295–300. http://dx.doi.org/10.4049/jimmunol.146.12.4295.

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Abstract The antimicrobial polypeptides Bac7 and Bac5 (bactenecins) are stored in the large granules of bovine neutrophils as precursor forms, or probactenecins. Maturation of probactenecins has been investigated by studying the effects of stimulus-induced degranulation on this process. Stimulation of neutrophils with PMA, which is a secretagogue for specific and large granules but not for azurophils, induces a substantial discharge of uncleaved probactenecins in the extracellular medium, as revealed by Western blot analysis. When neutrophils are exposed to opsonized bacteria in the presence of cytochalasin B, resulting in exocytosis of the content of azurophils in addition to that of specific and large granules, probactenecins are secreted and rapidly converted into the corresponding mature antimicrobial peptides. Such a conversion is prevented if serine proteases, stored in the azurophils, are inhibited by pretreatment of neutrophils with PMSF. Phagocytosis, while causing a rapid discharge of the contents of azurophil and of the large granules into phagocytic vacuoles, as indicated by immunogold electron microscopy, also induces cleavage of probactenecins into mature peptides, as revealed by Western blot analysis. We conclude that the final processing of the storage forms of bactenecins arises from their interaction with the serine protease(s) of azurophils during bacteria-induced degranulation of neutrophils.

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13

Scocchi, Marco, Christine Lüthy, Pietro Decarli, Giuseppina Mignogna, Philipp Christen, and Renato Gennaro. "The Proline-rich Antibacterial Peptide Bac7 Binds to and Inhibits in vitro the Molecular Chaperone DnaK." International Journal of Peptide Research and Therapeutics 15, no. 2 (May 13, 2009): 147–55. http://dx.doi.org/10.1007/s10989-009-9182-3.

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14

Malik, Amarila, Elita Yuliantie, Nisa Yulianti Suprahman, Theresa Linardi, Angelina Wening Widiyanti, Jeanita Haldy, Catherine Tjia, and Hiroshi Takagi. "Construction and Functional Analysis of the Recombinant Bacteriocins Weissellicin-MBF from Weissella confusa MBF8-1." Current Pharmaceutical Biotechnology 22, no. 1 (December 31, 2020): 115–22. http://dx.doi.org/10.2174/1389201021666200611111040.

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Background: Bacteriocins (Bac1, Bac2, and Bac3) from Weissella confusa MBF8-1, weissellicin- MBF, have been reported as potential alternative substances as well as complements to the existing antibiotics against many antimicrobial-resistant pathogens. Previously, the genes encoded in the large plasmid, pWcMBF8-1, and the spermicidal activity of their synthetic peptides, originally discovered Indonesia, have been studied. Three synthetic bacteriocins peptides of this weissellicin-MBF have been reported for their potential activities, i.e. antibacterial and spermicidal. Objective: The aim of this study was to construct the recombinant Bacteriocin (r-Bac) genes, as well as to investigate the gene expressions and their functional analysis. Method: Here, the recombinant Bacteriocin (r-Bac) genes were constructed and the recombinant peptides (r-Bac1, r-Bac2, and r-Bac3) in B. subtilis DB403 cells were produced on a large scale. After purification, using the His-tag affinity column, their potential bioactivities were measured as well as their antibacterial minimum inhibitory concentrations against Leuconostoc mesenteroides and Micrococcus luteus, were determined. Results: Pure His-tag-recombinant Bac1, Bac2, and Bac3 were obtained and they could inhibit the growth of L. mesenteroides and M. luteus. Conclusion: The recombinant bacteriocin could be obtained although with weak activity in inhibiting gram-positive bacterial growth.

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15

Ghiselli, Roberto, Andrea Giacometti, Oscar Cirioni, Raffaella Circo, Federico Mocchegiani, Barbara Skerlavaj, Giuseppina D'Amato, Giorgio Scalise, Margherita Zanetti, and Vittorio Saba. "Neutralization of Endotoxin In Vitro and In Vivo by BAC7(1-35), a Proline-Rich Antibacterial Peptide." Shock 19, no. 6 (June 2003): 577–81. http://dx.doi.org/10.1097/01.shk.0000055236.26446.c9.

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Ullah, Md Enayet, Farhana Tasnim Chowdhury, Sharaf Aroni, Al Amin, Maqsud Hossain, Haseena Khan, and Mohammad Riazul Islam. "Protease from jute endophyte Micrococcus luteus MBL-Bac7 functions as a potential bating agent for the leather industry." Journal of Bangladesh Academy of Sciences 46, no. 1 (June 29, 2022): 31–43. http://dx.doi.org/10.3329/jbas.v46i1.60345.

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Ever since the discovery of jute endophytes, testing their potential for commercial uses has been a matter of interest. Considering the same, jute endophyte Micrococcus luteus MBL-Bac7, capable of producing extracellular proteases, was selected for in vitro and in silico analysis to assess its role as a bating agent required in rawhide processing. The presence of extracellular protease was confirmed from the plate assay. As the enzyme is tested for commercial use, the effect of various metal ions and reaction conditions (pH, temperature) have been optimized. The protease activity appears to be retained even at 85°C. It also showed significant activity in a wide range of pH (pH 3.0-8.5). Metal ion Mn2+ increased the protease activity significantly, but Fe2+, Zn2+, and Co2+ ions showed the opposite effect. Molecular identification of the protease was done from the whole genome sequence data. Using PSORTb v.3.0.2, SecretomeP-1.0, TMHMM-2.0, and protein molecular weight software, the physicochemical properties of the protease were predicted. The isolated protease shared a strong evolutionary link with Micrococcus species' S8 family serine peptidase. Finally, in the bating of cowhide, effects similar to that of commercial agents were obtained during finger prick, lastometer, and tensile tests. The findings of this study corroborate the possibility of using this protease as a potential bating agent. However, further studies are necessary to reduce the production cost for higher yield and commercialization. J. Bangladesh Acad. Sci. 46(1); 31-43: June 2022

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17

Seefeldt, A. Carolin, Michael Graf, Natacha Pérébaskine, Fabian Nguyen, Stefan Arenz, Mario Mardirossian, Marco Scocchi, Daniel N. Wilson, and C. Axel Innis. "Structure of the mammalian antimicrobial peptide Bac7(1–16) bound within the exit tunnel of a bacterial ribosome." Nucleic Acids Research 44, no. 5 (January 20, 2016): 2429–38. http://dx.doi.org/10.1093/nar/gkv1545.

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18

Samizadeh, Mahta, Xiaoping Zhang, Simi Gunaseelan, Antoinette G. Nelson, Matthew S. Palombo, Daniel R. Myers, Yashveer Singh, Usha Ganapathi, Zoltan Szekely, and Patrick J. Sinko. "Colorectal delivery and retention of PEG-Amprenavir-Bac7 nanoconjugates—proof of concept for HIV mucosal pre-exposure prophylaxis." Drug Delivery and Translational Research 6, no. 1 (December 28, 2015): 1–16. http://dx.doi.org/10.1007/s13346-015-0269-4.

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19

Benincasa, Monica, Chiara Pelillo, Sonia Zorzet, Chiara Garrovo, Stefania Biffi, Renato Gennaro, and Marco Scocchi. "The proline-rich peptide Bac7(1-35) reduces mortality from Salmonella typhimurium in a mouse model of infection." BMC Microbiology 10, no. 1 (2010): 178. http://dx.doi.org/10.1186/1471-2180-10-178.

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20

Runti, G., M. d. C. Lopez Ruiz, T. Stoilova, R. Hussain, M. Jennions, H. G. Choudhury, M. Benincasa, R. Gennaro, K. Beis, and M. Scocchi. "Functional Characterization of SbmA, a Bacterial Inner Membrane Transporter Required for Importing the Antimicrobial Peptide Bac7(1-35)." Journal of Bacteriology 195, no. 23 (September 27, 2013): 5343–51. http://dx.doi.org/10.1128/jb.00818-13.

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21

Benincasa, Monica, Sotir Zahariev, Chiara Pelillo, Annalisa Milan, Renato Gennaro, and Marco Scocchi. "PEGylation of the peptide Bac7(1–35) reduces renal clearance while retaining antibacterial activity and bacterial cell penetration capacity." European Journal of Medicinal Chemistry 95 (May 2015): 210–19. http://dx.doi.org/10.1016/j.ejmech.2015.03.028.

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22

Guida, Filomena, Monica Benincasa, Sotir Zahariev, Marco Scocchi, Federico Berti, Renato Gennaro, and Alessandro Tossi. "Effect of Size and N-Terminal Residue Characteristics on Bacterial Cell Penetration and Antibacterial Activity of the Proline-Rich Peptide Bac7." Journal of Medicinal Chemistry 58, no. 3 (January 14, 2015): 1195–204. http://dx.doi.org/10.1021/jm501367p.

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23

Rey, María-Dolores, Graham Moore, and Azahara C. Martín. "Identification and comparison of individual chromosomes of three accessions of Hordeum chilense, Hordeum vulgare, and Triticum aestivum by FISH." Genome 61, no. 6 (June 2018): 387–96. http://dx.doi.org/10.1139/gen-2018-0016.

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Karyotypes of three accessions of Hordeum chilense (H1, H16, and H7), Hordeum vulgare, and Triticum aestivum were characterized by physical mapping of several repetitive sequences. A total of 14 repetitive sequences were used as probes for fluorescence in situ hybridization (FISH) with the aim of identifying inter- and intraspecies polymorphisms. The (AG)12 and 4P6 probes only produced hybridization signals in wheat, the BAC7 probe only hybridized to the centromeric region of H. vulgare, and the pSc119.2 probe hybridized to both wheat and H. chilense, but not to H. vulgare. The remaining repetitive sequences used in this study produced a hybridization signal in all the genotypes. Probes pAs1, pTa-535, pTa71, CCS1, and CRW were much conserved, showing no significant polymorphism among the genotypes studied. Probes GAA, (AAC)5, (CTA)5, HvT01, and pTa794 produced the most different hybridization pattern. We identified large polymorphisms in the three accessions of H. chilense studied, supporting the proposal of the existence of different groups inside species of H. chilense. The set of probes described in this work allowed the identification of every single chromosome in all three species, providing a complete cytogenetic karyotype of H. chilense, H. vulgare, and T. aestivum chromosomes, which could be useful in wheat and tritordeum breeding programs.

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Sartono, Gusti, Izzatu Rizqiyah, Asmarinah, Nicholas C. K. Heng, and Amarila Malik. "Three Bacteriocin Peptides from a Lactic Acid Bacterium Weissella confusa MBF8-1 with Spermicidal Activity." Current Pharmaceutical Biotechnology 20, no. 9 (September 6, 2019): 766–71. http://dx.doi.org/10.2174/1389201020666190617163310.

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Background:The development of antibiotic resistance amongst bacterial pathogens and a population explosion, e.g. in countries such as Indonesia, are two issues the world is facing today. These issues have stimulated interest in the development of new antimicrobial therapeutic agents and contraceptive strategies, such as novel spermicides. Bacteriocins, which are bacterially-derived antimicrobial peptides, may fulfill some of the criteria for these new agents.Methods:Weissella confusa MBF8-1, originally isolated from a homemade soy product, exhibits antibacterial activity that was subsequently found to be plasmid-encoded, presumably by three peptides Bac1, Bac2 and Bac3. In the present study, we tested cell-free MBF8-1 bacteriocin preparations and chemically-synthesized versions of Bac1, Bac2 and Bac3 peptides for (i) its antibacterial activity against the indicator bacterium Leuconostoc mesenteroides and (ii) its ability to affect the motility of spermatozoa. Nisin, a known lantibiotic bacteriocin, was used as the control.Results:Here, we demonstrate that synthetic Bac1, in combination with synthetic Bac2, was sufficient to inhibit the growth of L. mesenteroides and affect sperm motility. However, the presence of all three synthetic peptides, s-Bac1, s-Bac2 and s-Bac3, was required for full potency.Conclusion:In summary, the bacteriocin-like peptides of W. confusa MBF8-1 have the potential to be developed as a narrow-spectrum antimicrobial agent and a novel spermicidal agent.

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Pelillo, Chiara, Monica Benincasa, Marco Scocchi, Renato Gennaro, Alessandro Tossi, and Sabrina Pacor. "Cellular Internalization and Cytotoxicity of the Antimicrobial Proline-rich Peptide Bac7(1-35) in Monocytes/Macrophages, and its Activity Against Phagocytosed Salmonella typhimurium." Protein & Peptide Letters 21, no. 4 (February 2014): 382–90. http://dx.doi.org/10.2174/09298665113206660109.

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Panteleev, Pavel V., Victoria N. Safronova, Roman N. Kruglikov, Ilia A. Bolosov, Ivan V. Bogdanov, and Tatiana V. Ovchinnikova. "A Novel Proline-Rich Cathelicidin from the Alpaca Vicugna pacos with Potency to Combat Antibiotic-Resistant Bacteria: Mechanism of Action and the Functional Role of the C-Terminal Region." Membranes 12, no. 5 (May 12, 2022): 515. http://dx.doi.org/10.3390/membranes12050515.

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Over recent years, a growing number of bacterial species have become resistant to clinically relevant antibiotics. Proline-rich antimicrobial peptides (PrAMPs) having a potent antimicrobial activity and a negligible toxicity toward mammalian cells attract attention as new templates for the development of antibiotic drugs. Here, we mined genomes of all living Camelidae species and found a novel family of Bac7-like proline-rich cathelicidins which inhibited bacterial protein synthesis. The N-terminal region of a novel peptide from the alpaca Vicugna pacos named VicBac is responsible for inhibition of bacterial protein synthesis with an IC50 value of 0.5 µM in the E. coli cell-free system whereas the C-terminal region allows the peptide to penetrate bacterial membranes effectively. We also found that the full-length VicBac did not induce bacterial resistance after a two-week selection experiment, unlike the N-terminal truncated analog, which depended on the SbmA transport system. Both pro- and anti-inflammatory action of VicBac and its N-terminal truncated variant on various human cell types was found by multiplex immunoassay. The presence of the C-terminal tail in the natural VicBac does not provide for specific immune-modulatory effects in vitro but enhances the observed impact compared with the truncated analog. The pronounced antibacterial activity of VicBac, along with its moderate adverse effects on mammalian cells, make this molecule a promising scaffold for the development of peptide antibiotics.

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Shah, Pramod, and Chien-Sheng Chen. "Systematical Screening of Intracellular Protein Targets of Polyphemusin-I Using Escherichia coli Proteome Microarrays." International Journal of Molecular Sciences 22, no. 17 (August 25, 2021): 9158. http://dx.doi.org/10.3390/ijms22179158.

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With their wide repertoire of mechanisms, antimicrobial peptides (AMPs) are promising alternatives to fight against varied pathogenic microorganisms (bacteria, fungi, viruses, parasites, etc.). AMPs, novel components of the innate immune defense system, are secreted by all organisms. The aquatic environment represents a huge population and an enormous source of varied AMPs. Polyphemusin-I, a marine AMP isolated from hemocytes of an American horseshoe crab, possesses high antimicrobial activities. Studies on polyphemusin-I have verified the intracellular mechanisms of action, however, its intracellular targets are not yet explored. In this study, we employed Escherichia coli proteome microarrays to systematically screen the entire intracellular protein targets of polyphemusin-I. A total of 97 protein targets of polyphemusin-I were statistically analyzed from the quadruplicate Escherichia coli proteome microarrays assays. Among these identified protein targets, 56 proteins had cellular location inside the cell (i.e., cytoplasm), one in the plasma membrane, one in the periplasm and the rest 39 proteins had no specified cellular location. The bioinformatics analysis of these identified protein targets of polyphemusin-I in gene ontology (GO) enrichment category of molecular function revealed significant enrichment in nucleic acid related GO terms i.e., “RNA binding”, “nucleotide binding”, “nuclease activities”, “uracil DNA N-glycosylase activities” and others. Moreover, enrichment in GO category of biological process also depicted enrichment in nucleic acid related GO terms, such as “nucleic acid phosphodiester bond hydrolysis”, “deoxyribonucleotide metabolism”, and others. In accordance to GO enrichment analysis, protein families (PFAM) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways enrichment analysis also showed significant enrichment in nucleic acid terms. These enrichment results suggest that polyphemusin-I targets nucleic acid-associated proteins. Furthermore, to provide a comprehensive study, we compared the identified protein targets of polyphemusin-I with previously identified protein targets of four AMPs (P-Der, Lfcin B, PR-39, and Bac 7) using Escherichia coli proteome microarrays. The comparison study of five AMPs (polyhemusin-I, P-Der, Lfcin B, PR-39, and Bac 7) showed only nine common protein targets in all the five AMPs, whereas a total of 39 and 43 common protein targets were identified among the two marine AMPs (polyphemusin-I and P-Der) and three terrestrial AMPs (Lfcin B, PR-39 and Bac7), respectively. To further reveal the target pattern of marine and terrestrial AMPs, the enrichment results obtained from common protein targets of marine AMPs with terrestrial AMPs were compared. The comparison result indicated that AMPs have unique mechanism of action among marine or terrestrial AMPs. Hence, in this study, we have not only identified the intracellular protein targets of polyphemusin-I, but also revealed the protein target differences between marine AMPs and terrestrial AMPs.

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Inoue, Takako, Haruyoshi Tomita, and Yasuyoshi Ike. "Bac 32, a Novel Bacteriocin Widely Disseminated among Clinical Isolates of Enterococcus faecium." Antimicrobial Agents and Chemotherapy 50, no. 4 (April 2006): 1202–12. http://dx.doi.org/10.1128/aac.50.4.1202-1212.2006.

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ABSTRACT A total of 636 vancomycin-resistant Enterococcus faecium (VRE) isolates that had been obtained between 1994 and 1999 from the Medical School Hospital of the University of Michigan, Ann Arbor, were tested for bacteriocin production. Two hundred seventy-seven (44%) of the strains were bacteriocinogenic; and 193 of these exhibited activity against Enterococcus faecium, Enterococcus hirae, and Enterococcus durans. Strain VRE200 harbors the highly efficient conjugative gentamicin resistance plasmid pG200 (70 kb) and bacteriocin plasmid pTI1 (12.5 kb). The bacteriocin encoded on pTI1 was designated bacteriocin 32 (Bac 32). Bacteriocin 32 was active against E. faecium, E. hirae, and E. durans but showed no activity against Listeria monocytogenes. The Bac 32 genetic locus consists of a bacteriocin gene (bacA) and an immunity gene (bacB). Neither of these genes showed significant homology to any known bacteriocin determinants. The deduced bacA product is 89 amino acids in length, with a putative signal peptide of 19 amino acids at the N terminus. The bacB gene encodes a deduced 55-amino-acid protein without a signal sequence. One hundred eighty-nine strains (97.9%) of the 193 strains with activity against the 3 test enterococcal strains gave rise to the expected specific PCR product with a primer specific for bacA, indicating that there is a high incidence of Bac 32 production among VRE clinical isolates. Data from Southern analyses of plasmid DNA from 189 of the Bac 32-producing strains with a plasmid pTI1-specific probe suggested that 137 (72.5%) of the strains harbored a pTI1-type plasmid. Bac 32 or Bac 32-type bacteriocin activity and the determinant genes were also identified in 22 (39.3%) of a total of 56 vancomycin-sensitive E. faecium clinical isolates, which suggests that this bacteriocin is widely disseminated among E. faecium strains.

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Murrell, Isa, Gavin S. Wilkie, Andrew J. Davison, Evelina Statkute, Ceri A. Fielding, Peter Tomasec, Gavin W. G. Wilkinson, and Richard J. Stanton. "Genetic Stability of Bacterial Artificial Chromosome-Derived Human Cytomegalovirus during CultureIn Vitro." Journal of Virology 90, no. 8 (February 3, 2016): 3929–43. http://dx.doi.org/10.1128/jvi.02858-15.

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ABSTRACTClinical human cytomegalovirus (HCMV) strains invariably mutate when propagatedin vitro. Mutations in gene RL13 are selected in all cell types, whereas in fibroblasts mutants in the UL128 locus (UL128L; genes UL128, UL130, and UL131A) are also selected. In addition, sporadic mutations are selected elsewhere in the genome in all cell types. We sought to investigate conditions under which HCMV can be propagated without incurring genetic defects. Bacterial artificial chromosomes (BACs) provide a stable, genetically defined source of viral genome. Viruses were generated from BACs containing the genomes of strains TR, TB40, FIX, and Merlin, as well as from Merlin-BAC recombinants containing variant nucleotides in UL128L from TB40-BAC4 or FIX-BAC. Propagation of viruses derived from TR-BAC, TB40-BAC4, and FIX-BAC in either fibroblast or epithelial cells was associated with the generation of defects around the prokaryotic vector, which is retained in the unique short (US) region of viruses. This was not observed for Merlin-BAC, from which the vector is excised in derived viruses; however, propagation in epithelial cells was consistently associated with mutations in the unique longb′ (UL/b′) region, all impacting on gene UL141. Viruses derived from Merlin-BAC in fibroblasts had mutations in UL128L, but mutations occurred less frequently with recombinants containing UL128L nucleotides from TB40-BAC4 or FIX-BAC. Viruses derived from a Merlin-BAC derivative in which RL13 and UL128L were either mutated or repressed were remarkably stable in fibroblasts. Thus, HCMV containing a wild-type gene complement can be generatedin vitroby deriving virus from a self-excising BAC in fibroblasts and repressing RL13 and UL128L.IMPORTANCEResearchers should aim to study viruses that accurately represent the causative agents of disease. This is problematic for HCMV because clinical strains mutate rapidly when propagatedin vitro, becoming less cell associated, altered in tropism, more susceptible to natural killer cells, and less pathogenic. Following isolation from clinical material, HCMV genomes can be stabilized by cloning into bacterial artificial chromosomes (BACs), and then virus is regenerated by DNA transfection. However, mutations can occur not only during isolation prior to BAC cloning but also when virus is regenerated. We have identified conditions under which BAC-derived viruses containing an intact, wild-type genome can be propagatedin vitrowith minimal risk of mutants being selected, enabling studies of viruses expressing the gene complement of a clinical strain. However, even under these optimized conditions, sporadic mutations can occur, highlighting the advisability of sequencing the HCMV stocks used in experiments.

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Anderson, Robert, CPE Bach, and Stephen L. Clark. "Back to Bach." Musical Times 139, no. 1860 (February 1998): 34. http://dx.doi.org/10.2307/1004294.

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Van de Wiel, Albert, David Moolenaar, and Jos Wielders. "The Bac(chus) experiment: blood alcohol concentrations after wine tasting." Wine Studies 2, no. 1 (March 8, 2012): 1. http://dx.doi.org/10.4081/ws.2012.e1.

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Blood alcohol concentrations (BACs) were measured in ten volunteers after a wine tasting event with and without the swallowing of 15 mL of each wine. In case ten wines were tasted within one hour without swallowing, buccal mucosa absorption did not result in problematic BAC’s; however in case 15 mL of each wine was swallowed, BAC’s may exceed the legal driving limit of most countries. It is recommended to eat beforehand, but also to wait at least one hour after the session before driving back home.

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Desmiarti, Reni, Yoji Morishita, Tomonari Fujisawa, Yasushi Ishiguro, Toshiro Yamada, and Fusheng Li. "Characteristics of Nanoparticles in Drinking Water Treatment using Biological Activated Carbon." MATEC Web of Conferences 156 (2018): 03039. http://dx.doi.org/10.1051/matecconf/201815603039.

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Characteristics of nanoparticles in drinking water treatment were performed using five types of biological activated carbon (BAC) columns (BAC1-BAC5) in continuous flow experiments. The BAC was created by covering granular activated carbon (GAC) with attached microorganisms from water samples taken from the Nagara River in Japan. The total running time was about 2000 h. The characteristics of the nanoparticles were investigated based on size distribution and volume distribution measured by Zetasizer Nano. Total dissolved organic carbon (DOC) and ultraviolet absorbance at 260 nm (UV260) were also studied. The important results in this study were that the detached nanoparticles in the effluent were within the size distribution ranges of 0.26~5.62 nm, 0.62~3.62 nm, 0.62~3.12 nm, 0.62~4.19 nm, and 0.62~6.50 for BAC 1, 2, 3, 4 and 5, respectively. The profile of peak size and peak number along the bed depth of the BAC columns was evaluated for better understanding the characteristics of the nanoparticles. This result is very important for improving drinking water treatment using granular activated carbon to remove microorganisms.

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Penny, Simon. "From Bacteria to Bach and Back." AI & SOCIETY 34, no. 2 (January 30, 2018): 383–86. http://dx.doi.org/10.1007/s00146-018-0797-9.

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Lee, Hyeseung, and Myriam Heiman. "Back-to-BACs in Huntington’s disease modeling." Neuron 110, no. 7 (April 2022): 1087–89. http://dx.doi.org/10.1016/j.neuron.2022.02.022.

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Amoo, Temiloluwa E., Kehinde O. Amoo, Opeyemi A. Adeeyo, and Clement O. Ogidi. "Kinetics and Equilibrium Studies of the Adsorption of Copper(II) Ions from Industrial Wastewater Using Activated Carbons Derived from Sugarcane Bagasse." International Journal of Chemical Engineering 2022 (April 23, 2022): 1–24. http://dx.doi.org/10.1155/2022/6928568.

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The monocomponent adsorption process of Cu(II) ions in synthesized industrial wastewater were investigated using activated carbons (BACs) derived from sugarcane bagasse as the precursor. Batch adsorption studies were done by treating the precursor with H3PO4 (BAC-P) and ZnCl2 (BAC-Zn) in order to observe the effects of experimental variables such as contact time, pH of the solution, and adsorbent dose. The Langmuir isotherm model excellently described the adsorption data for both the derived BACs, indicating monolayer coverage on the BACs with the determination coefficients close to the value of one. Furthermore, the maximum adsorption capacities of 589 and 225 m g g − 1 at 30°C were obtained for BAC-P and BAC-Zn adsorbents, respectively. The modeling of kinetic data of Cu(II) ions adsorption onto BAC-P and BAC-Zn adsorbents illustrated that the Elovich kinetic model fitted well. Here, the adsorption process was film-diffusion controlling, while being principally governed by external mass transport where the slowest step is the diffusion of the particles through the film layer. The mechanism of the adsorption process was proposed taking into cognizance of the ion exchange and surface complexation on active sites between the negatively charged surface of the BACs and the positively charged Cu(II) ions. The BACs were characterized using analytical methods such as SEM, FTIR, EDX, XRD, BET surface area, and zeta potential measurements. Both BACs mainly composed of mesopores and bonds of O-H, C-O, C=O, and C-O-C. The BET surface area of BAC-P and BAC-Zn was 427.5 and 282 m2/g before adsorption, and their isoelectric point (pHIEP) 3.70 and 5.26, respectively.

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Sinzger, Christian, Gabriele Hahn, Margarete Digel, Ruth Katona, Kerstin Laib Sampaio, Martin Messerle, Hartmut Hengel, Ulrich Koszinowski, Wolfram Brune, and Barbara Adler. "Cloning and sequencing of a highly productive, endotheliotropic virus strain derived from human cytomegalovirus TB40/E." Journal of General Virology 89, no. 2 (February 1, 2008): 359–68. http://dx.doi.org/10.1099/vir.0.83286-0.

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Human cytomegalovirus (HCMV) strain TB40/E, replicates efficiently, exhibits a broad cell tropism and is widely used for infection of endothelial cells and monocyte-derived cells yet has not been available in a phenotypically homogeneous form compatible with genetic analysis. To overcome this problem, we cloned the TB40/E strain into a bacterial artificial chromosome (BAC) vector. Both highly endotheliotropic and poorly endotheliotropic virus clones, representing three distinct restriction fragment patterns, were reconstituted after transfection of BAC clones derived from previously plaque-purified strain TB40/E. For one of the highly endotheliotropic clones, TB40-BAC4, we provide the genome sequence. Two BACs with identical restriction fragment patterns but different cell tropism were further analysed in the UL128-UL131A gene region. Sequence analysis revealed one coding-relevant adenine insertion at position 332 of UL128 in the BAC of the poorly endotheliotropic virus, which caused a frameshift in the C-terminal part of the coding sequence. Removal of this insertion by markerless mutagenesis restored the highly endotheliotropic phenotype, indicating that the loss of endothelial cell tropism was caused by this insertion. In conclusion, HCMV strain TB40/E, which combines the high endothelial cell tropism of a clinical isolate with the high titre growth of a cell culture adapted strain, is now available as a BAC clone suitable for genetic engineering. The results also suggest BAC cloning as a suitable method for selection of genetically defined virus clones.

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Oh, Seungdae, Zohre Kurt, Despina Tsementzi, Michael R. Weigand, Minjae Kim, Janet K. Hatt, Madan Tandukar, Spyros G. Pavlostathis, Jim C. Spain, and Konstantinos T. Konstantinidis. "Microbial Community Degradation of Widely Used Quaternary Ammonium Disinfectants." Applied and Environmental Microbiology 80, no. 19 (June 20, 2014): 5892–900. http://dx.doi.org/10.1128/aem.01255-14.

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ABSTRACTBenzalkonium chlorides (BACs) are disinfectants widely used in a variety of clinical and environmental settings to prevent microbial infections, and they are frequently detected in nontarget environments, such as aquatic and engineered biological systems, even at toxic levels. Therefore, microbial degradation of BACs has important ramifications for alleviating disinfectant toxicity in nontarget environments as well as compromising disinfectant efficacy in target environments. However, how natural microbial communities respond to BAC exposure and what genes underlie BAC biodegradation remain elusive. Our previous metagenomic analysis of a river sediment microbial community revealed that BAC exposure selected for a low-diversity community, dominated by several members of thePseudomonasgenus that quickly degraded BACs. To elucidate the genetic determinants of BAC degradation, we conducted time-series metatranscriptomic analysis of this microbial community during a complete feeding cycle with BACs as the sole carbon and energy source under aerobic conditions. Metatranscriptomic profiles revealed a candidate gene for BAC dealkylation, the first step in BAC biodegradation that results in a product 500 times less toxic. Subsequent biochemical assays and isolate characterization verified that the putative amine oxidase gene product was functionally capable of initiating BAC degradation. Our analysis also revealed cooperative interactions among community members to alleviate BAC toxicity, such as the further degradation of BAC dealkylation by-products by organisms not encoding amine oxidase. Collectively, our results advance the understanding of BAC aerobic biodegradation and provide genetic biomarkers to assess the critical first step of this process in nontarget environments.

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Bradley, Peter. "Back to BACE: one approach to fighting Alzheimer's." British Journal of Healthcare Assistants 11, no. 1 (January 2, 2017): 10–11. http://dx.doi.org/10.12968/bjha.2017.11.1.10.

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Yamashita, Hitoshi, Haruyoshi Tomita, Takako Inoue, and Yasuyoshi Ike. "Genetic Organization and Mode of Action of a Novel Bacteriocin, Bacteriocin 51: Determinant of VanA-Type Vancomycin-Resistant Enterococcus faecium." Antimicrobial Agents and Chemotherapy 55, no. 9 (June 27, 2011): 4352–60. http://dx.doi.org/10.1128/aac.01274-10.

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ABSTRACTBacteriocin 51 (Bac 51) is encoded on the mobile plasmid pHY (6,037 bp), which was isolated from vancomycin-resistantEnterococcus faeciumVRE38. Bacteriocin 51 is active againstE. faecium,E. hirae, andE. durans. Sequence analysis of pHY showed that it encodes nine open reading frames (ORFs) from ORF1 to ORF9 (in that order). Genetic analysis suggested that ORF1 and ORF2, which were designatedbacAandbacB, respectively, are the bacteriocin and immunity genes.bacAencodes a 144-amino-acid protein. The deduced BacA protein has a typical signal sequence at its amino terminus, and a potential signal peptidase-processing site corresponding to the V-E-A sequence is located between the 37th and 39th amino acids. The predicted mature BacA protein consists of 105 amino acids. A potential promoter sequence was identified upstream of the start codon.bacBencodes a 55-amino-acid protein. No obvious promoter or terminator sequence was identified betweenbacAandbacB. Northern blot analysis ofbacAandbacBwith abacARNA probe produced a transcript of approximately 700 nucleotides, which corresponded to the combined nucleotide sizes ofbacAandbacB, indicating that transcription was initiated from the promoter upstream ofbacA, continued throughbacB, and was terminated at the terminator downstream ofbacB. The transcription start site was determined to be the T nucleotide located 6 nucleotides downstream from the −10 promoter sequence. These results indicate thatbacAandbacBconstitute an operon and thatbacAis the bacteriocin structural gene whilebacBis the immunity gene. The purified C-terminally His tagged BacA protein of Bac 51 showed bacteriostatic activity against the indicator strain. The purified C-terminally His tagged BacA protein of Bac 32 (whose mature BacA protein has 54 amino acids) and the culture filtrates of the Bac 31- and Bac 43-producingE. faecalisstrain FA2-2 showed bactericidal activity. Bac 31 and Bac 43 are pore-forming bacteriocins, unlike the newly characterized bacteriocin Bac 51.

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TEKNIK, Editor in Chief. "Back Matter." TEKNIK 42, no. 1 (May 10, 2021): 1–5. http://dx.doi.org/10.14710/teknik.v42i1.38718.

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TEKNIK, Editor in Chief. "Back Matter." TEKNIK 41, no. 3 (December 31, 2020): 1–5. http://dx.doi.org/10.14710/teknik.v41i3.35434.

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Vergnies, Jean-Frédéric. "Édito : Du Bac pro… aux Bacs pros." Formation emploi, no. 131 (October 15, 2015): 1–2. http://dx.doi.org/10.4000/formationemploi.4444.

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Cao, Yicheng, Hyung Lyun Kang, Xuequn Xu, Mei Wang, So Hee Dho, Jun Ryul Huh, Byeong-Jae Lee, et al. "A 12-Mb Complete Coverage BAC Contig Map in Human Chromosome 16p13.1–p11.2." Genome Research 9, no. 8 (August 1, 1999): 763–74. http://dx.doi.org/10.1101/gr.9.8.763.

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We have constructed a complete coverage BAC contig map that spans a 12-Mb genomic segment in the human chromosome 16p13.1–p11.2 region. The map consists of 68 previously mapped STSs and 289 BAC clones, 51 of which—corresponding to a total of 7.721 Mb of genomic DNA—have been sequenced, and provides a high resolution physical map of the region. Contigs were initially built based mainly on the analysis of STS contents and restriction fingerprint patterns of the clones. To close the gaps, probes derived from BAC clone ends were used to screen deeper BAC libraries. Clone end sequence data obtained from chromosome 16-specific BACs, as well as from public databases, were used for the identification of BACs that overlap with fully sequenced BACs by means of sequence match. This approach allowed precise alignment of clone overlaps in addition to restriction fingerprint comparison. A freehand contig drawing software tool was developed and used to manage the map data graphically and generate a real scale physical map. The map we present here is ∼3.5 × deep and provides a minimal tiling path that covers the region in an array of contigous, overlapping BACs.

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Kuhl, Heiner, Elena Sarropoulou, Mbaye Tine, Georgios Kotoulas, Antonios Magoulas, and Richard Reinhardt. "A Comparative BAC Map for the Gilthead Sea Bream (Sparus aurataL.)." Journal of Biomedicine and Biotechnology 2011 (2011): 1–7. http://dx.doi.org/10.1155/2011/329025.

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This study presents the first comparative BAC map of the gilthead sea bream (Sparus aurata), a highly valuated marine aquaculture fish species in the Mediterranean. High-throughput end sequencing of a BAC library yielded 92,468 reads (60.6 Mbp). Comparative mapping was achieved by anchoring BAC end sequences to the three-spined stickleback (Gasterosteus aculeatus) genome. BACs that were consistently ordered along the stickleback chromosomes accounted for 14,265 clones. A fraction of 5,249 BACs constituted a minimal tiling path that covers 73.5% of the stickleback chromosomes and 70.2% of the genes that have been annotated. The N50 size of 1,485 “BACtigs” consisting of redundant BACs is 337,253 bp. The largest BACtig covers 2.15 Mbp in the stickleback genome. According to the insert size distribution of mapped BACs the sea bream genome is 1.71-fold larger than the stickleback genome. These results represent a valuable tool to researchers in the field and may support future projects to elucidate the whole sea bream genome.

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Eljamel, M. Sam. "Ablative neurosurgery for mental disorders: is there still a role in the 21st century? A personal perspective." Neurosurgical Focus 25, no. 1 (July 2008): E4. http://dx.doi.org/10.3171/foc/2008/25/7/e4.

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ObjectThe author presents his personal perspective on ablative neurosurgical techniques used to perform bilateral anterior cingulotomy (BACI) and bilateral anterior capsulotomy (BACA) for ameliorating the symptoms of refractory obsessive-compulsive disorder (OCD) and treatment refractory depression (TRD). With depression predicted to be the second most common cause of disability in the world by the year 2020 and the birth of electric neurostimulation representing an attractive alternative treatment option for TRD and OCD, it is desirable to revisit the pros and cons of these treatment options.MethodsThe author reviewed the surgical methods and outcome (including neuroimaging findings) in all cases in which ablative neurosurgery was performed at Ninewells Hospital and Medical School over the last 2 decades.ResultsThe advantages of ablative procedures (BACI and BACA) from patients’ and psychiatrists’ perspectives are that the ablative procedures are one-off procedures that do not require lifelong commitment to program the stimulation devices, fix hardware failures, or change exhausted batteries. From the perspective of healthcare funding bodies, the relatively low cost of these treatments is an advantage. The main disadvantages of BACI and BACA are the perceived higher complication rates, the irreversibility of the surgical lesions, and the stigma associated with brain destruction in psychiatric patients that are still unpalatable in the community at large. However, some patients still choose a one-off procedure in preference to any other options presented to them.ConclusionsThere is still place for BACI and BACA in modern neurosurgery for mental disorders, at least in the short term for those who do not want to commit to lifelong device programming and maintenance.

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Schumacher, Daniel, B. Karsten Tischer, Walter Fuchs, and Nikolaus Osterrieder. "Reconstitution of Marek's Disease Virus Serotype 1 (MDV-1) from DNA Cloned as a Bacterial Artificial Chromosome and Characterization of a Glycoprotein B-Negative MDV-1 Mutant." Journal of Virology 74, no. 23 (December 1, 2000): 11088–98. http://dx.doi.org/10.1128/jvi.74.23.11088-11098.2000.

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ABSTRACT The complete genome of Marek's disease virus serotype 1 (MDV-1) strain 584Ap80C was cloned in Escherichia coli as a bacterial artificial chromosome (BAC). BAC vector sequences were introduced into the US2 locus of the MDV-1 genome by homologous recombination. Viral DNA containing the BAC vector was used to transform Escherichia coli strain DH10B, and several colonies harboring the complete MDV-1 genome as an F plasmid (MDV-1 BACs) were identified. DNA from various MDV-1 BACs was transfected into chicken embryo fibroblasts, and from 3 days after transfection, infectious MDV-1 was obtained. Growth of MDV-1 recovered from BACs was indistinguishable from that of the parental virus, as assessed by plaque formation and determination of growth curves. In one of the MDV-1 BAC clones, sequences encoding glycoprotein B (gB) were deleted by one-step mutagenesis using a linear DNA fragment amplified by PCR. Mutant MDV-1 recovered after transfection of BAC DNA that harbored a 2.0-kbp deletion of the 2.6-kbp gB gene were able to grow and induce MDV-1-specific plaques only on cells providing MDV-1 gB in trans. The gB-negative virus reported here represents the first MDV-1 mutant with a deletion of an essential gene and demonstrates the power and usefulness of BACs to analyze genes and gene products in slowly growing and strictly cell-associated herpesviruses.

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Vanegas Moreno, David. "Dennett. D. (2017). From Bacteria to Bach and Back." Estudios de Filosofía, no. 59 (January 2019): 255–62. http://dx.doi.org/10.17533/udea.ef.n59a12.

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Wang, Min Qi, Mary E. Nicholson, Beverly S. Mahoney, Yuhua Li, and Mike A. Perko. "Proprioceptive Responses under Rising and Falling BACs: A Test of the Mellanby Effect." Perceptual and Motor Skills 77, no. 1 (August 1993): 83–88. http://dx.doi.org/10.2466/pms.1993.77.1.83.

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This study examined proprioceptive responses under equivalent rising and falling blood alcohol concentrations (BAC), using a repeated-measures design. Seven volunteer subjects, 21 to 35 years of age, participated in the study. After alcohol consumption, BAC readings were obtained every 5 minutes, and the proprioceptive responses were measured at the following BAC levels (in %): 0 (baseline), rising 0.05, 0.075, 0.1, falling 0.075, and 0.05. The analysis focused on the comparisons of these measures at the equivalent rising and falling 0.05% and at the 0.075% BACs. Results showed that the proprioceptive response was less accurate during the rising than the falling BACs.

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Yin, Ningning, Jinhuan Zhong, Huayu Tian, Zenan Zhou, Weijun Ying, Jinfeng Dai, Wenzhu Li, and Wenbiao Zhang. "Synthesis of P-/N-Containing Bamboo-Activated Carbon toward Enhanced Thermal Stability and Flame Retardancy of Polylactic Acid." Materials 15, no. 19 (September 30, 2022): 6802. http://dx.doi.org/10.3390/ma15196802.

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A P-/N-containing bamboo-activated carbon (BACm) was successfully synthesized by steam activation of bamboo charcoal and chemical grafting to as-prepared activated carbon using the reaction of phosphoric acid and urea. Characterizations of BACm presented a synergistic grafting of P and N elements to the BAC surface. The BACm was further loaded in a polylactic acid (PLA) matrix to prepare BACm/PLA composites. Mechanical strength study showed tensile strength dropped from 75.19 MPa to 61.30 MPa, and tensile modulus from 602.49 MPa to 375.56 MPa, suggesting a rigidity reduction and deformation resistance enhancement owing to the roughened surface of BACm that interlocked with the polymer. The thermogravimetric analysis showed that the carbon residue rate of BACm dramatically fell to 49.25 wt.% in contrast to 88.28% for the control BAC, and cone calorimeter measurements confirmed the enhancement of flame retardancy of the composites with BACm loading, and the carbon residue rate increased progressively with BACm loading in the composites, notably up to 8.60 wt.% for the BAC/PLA9 composite, which outweighed the theoretical residue rate by more than 50%. The elemental analysis also confirmed rich P/N levels of the dense carbon residue layer that could perform synergistically and effectively in fire suppression. The BACm tended to stimulate the earlier decomposition of the composites and formed a continuous residual carbon layer which functioned as an effective barrier hindering the mass and heat transfer between the combustion zone and the underlying matrix. Moreover, 9 wt.% of BACm loading could attain a V-0 rating (UL94) for the composite with an improved limiting oxygen index up to 31.7%. The biomass-based modified activated carbon in this work could be considered as an alternative flame retardant in polymer applications.

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Marek, Laura Fredrick, Joann Mudge, Laura Darnielle, David Grant, Nadja Hanson, Margie Paz, Yan Huihuang, et al. "Soybean genomic survey: BAC-end sequences near RFLP and SSR markers." Genome 44, no. 4 (August 1, 2001): 572–81. http://dx.doi.org/10.1139/g01-052.

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We are building a framework physical infrastructure across the soybean genome by using SSR (simple sequence repeat) and RFLP (restriction fragment length polymorphism) markers to identify BACs (bacterial artificial chromosomes) from two soybean BAC libraries. The libraries were prepared from two genotypes, each digested with a different restriction enzyme. The BACs identified by each marker were grouped into contigs. We have obtained BAC-end sequence from BACs within each contig. The sequences were analyzed by the University of Minnesota Center for Computational Genomics and Bioinformatics using BLAST algorithms to search nucleotide and protein databases. The SSR-identified BACs had a higher percentage of significant BLAST hits than did the RFLP-identified BACs. This difference was due to a higher percentage of hits to repetitive-type sequences for the SSR-identified BACs that was offset in part, however, by a somewhat larger proportion of RFLP-identified significant hits with similarity to experimentally defined genes and soybean ESTs (expressed sequence tags). These genes represented a wide range of metabolic functions. In these analyses, only repetitive sequences from SSR-identified contigs appeared to be clustered. The BAC-end sequences also allowed us to identify microsynteny between soybean and the model plants Arabidopsis thaliana and Medicago truncatula. This map-based approach to genome sampling provides a means of assaying soybean genome structure and organization.Key words: Glycine max, sequencing, physical map, contig.

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Journal articles on the topic 'Bac7'

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