Journal of Bacteriology最新文献

{"title":"The <i>Bacillus subtilis yqgC-sodA</i> operon protects magnesium-dependent enzymes by supporting manganese efflux.","authors":"Ankita J Sachla, Vijay Soni, Miguel Piñeros, Yuanchan Luo, Janice J Im, Kyu Y Rhee, John D Helmann","doi":"10.1128/jb.00052-24","DOIUrl":"10.1128/jb.00052-24","url":null,"abstract":"<p><p>Microbes encounter a myriad of stresses during their life cycle. Dysregulation of metal ion homeostasis is increasingly recognized as a key factor in host-microbe interactions. Bacterial metal ion homeostasis is tightly regulated by dedicated metalloregulators that control uptake, sequestration, trafficking, and efflux. Here, we demonstrate that deletion of the <i>Bacillus subtilis yqgC-sodA</i> (YS) complex operon, but not deletion of the individual genes, causes hypersensitivity to manganese (Mn). YqgC is an integral membrane protein of unknown function, and SodA is a Mn-dependent superoxide dismutase (MnSOD). The YS strain has reduced expression of two Mn efflux proteins, MneP and MneS, consistent with the observed Mn sensitivity. The YS strain accumulated high levels of Mn, had increased reactive radical species (RRS), and had broad metabolic alterations that can be partially explained by the inhibition of Mg-dependent enzymes. Although the YS operon deletion strain and an efflux-deficient <i>mneP mneS</i> double mutant both accumulate Mn and have similar metabolic perturbations, they also display phenotypic differences. Several mutations that suppressed Mn intoxication of the <i>mneP mneS</i> efflux mutant did not benefit the YS mutant. Further, Mn intoxication in the YS mutant, but not the <i>mneP mneS</i> strain, was alleviated by expression of Mg-dependent, chorismate-utilizing enzymes of the <u>m</u>enaquinone, <u>s</u>iderophore, and <u>t</u>ryptophan (MST) family. Therefore, despite their phenotypic similarities, the Mn sensitivity in the <i>mneP mneS</i> and the YS deletion mutants results from distinct enzymatic vulnerabilities.IMPORTANCEBacteria require multiple trace metal ions for survival. Metal homeostasis relies on the tightly regulated expression of metal uptake, storage, and efflux proteins. Metal intoxication occurs when metal homeostasis is perturbed and often results from enzyme mis-metalation. In <i>Bacillus subtilis</i>, Mn-dependent superoxide dismutase (MnSOD) is the most abundant Mn-containing protein and is important for oxidative stress resistance. Here, we report novel roles for MnSOD and a co-regulated membrane protein, YqgC, in Mn homeostasis. Loss of both MnSOD and YqgC (but not the individual proteins) prevents the efficient expression of Mn efflux proteins and leads to a large-scale perturbation of the metabolome due to inhibition of Mg-dependent enzymes, including key chorismate-utilizing MST (menaquinone, siderophore, and tryptophan) family enzymes.</p>","PeriodicalId":15107,"journal":{"name":"Journal of Bacteriology","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11332163/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141179678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identifying components of the <i>Shewanella</i> phage LambdaSo lysis system.","authors":"Svenja Thöneböhn, Dorian Fischer, Vanessa Kreiling, Alina Kemmler, Isabella Oberheim, Fabian Hager, Nicole E Schmid, Kai M Thormann","doi":"10.1128/jb.00022-24","DOIUrl":"10.1128/jb.00022-24","url":null,"abstract":"<p><p>Phage-induced lysis of Gram-negative bacterial hosts usually requires a set of phage lysis proteins, a holin, an endopeptidase, and a spanin system, to disrupt each of the three cell envelope layers. Genome annotations and previous studies identified a gene region in the <i>Shewanella oneidensis</i> prophage LambdaSo, which comprises potential holin- and endolysin-encoding genes but lacks an obvious spanin system. By a combination of candidate approaches, mutant screening, characterization, and microscopy, we found that LambdaSo uses a pinholin/signal-anchor-release (SAR) endolysin system to induce proton leakage and degradation of the cell wall. Between the corresponding genes, we found that two extensively nested open-reading frames encode a two-component spanin module Rz/Rz1. Unexpectedly, we identified another factor strictly required for LambdaSo-induced cell lysis, the phage protein Lcc6. Lcc6 is a transmembrane protein of 65 amino acid residues with hitherto unknown function, which acts at the level of holin in the cytoplasmic membrane to allow endolysin release. Thus, LambdaSo-mediated cell lysis requires at least four protein factors (pinholin, SAR endolysin, spanin, and Lcc6). The findings further extend the known repertoire of phage proteins involved in host lysis and phage egress.</p><p><strong>Importance: </strong>Lysis of bacteria can have multiple consequences, such as the release of host DNA to foster robust biofilm. Phage-induced lysis of Gram-negative cells requires the disruption of three layers, the outer and inner membranes and the cell wall. In most cases, the lysis systems of phages infecting Gram-negative cells comprise holins to disrupt or depolarize the membrane, thereby releasing or activating endolysins, which then degrade the cell wall. This, in turn, allows the spanins to become active and fuse outer and inner membranes, completing cell envelope disruption and allowing phage egress. Here, we show that the presence of these three components may not be sufficient to allow cell lysis, implicating that also in known phages, further factors may be required.</p>","PeriodicalId":15107,"journal":{"name":"Journal of Bacteriology","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11332162/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141071037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biological puzzles solved by using <i>Streptococcus pneumoniae</i>: a historical review of the pneumococcal studies that have impacted medicine and shaped molecular bacteriology.","authors":"N Luisa Hiller, Carlos J Orihuela","doi":"10.1128/jb.00059-24","DOIUrl":"10.1128/jb.00059-24","url":null,"abstract":"<p><p>The major human pathogen <i>Streptococcus pneumoniae</i> has been the subject of intensive clinical and basic scientific study for over 140 years. In multiple instances, these efforts have resulted in major breakthroughs in our understanding of basic biological principles as well as fundamental tenets of bacterial pathogenesis, immunology, vaccinology, and genetics. Discoveries made with <i>S. pneumoniae</i> have led to multiple major public health victories that have saved the lives of millions. Studies on <i>S. pneumoniae</i> continue today, where this bacterium is being used to dissect the impact of the host on disease processes, as a powerful cell biology model, and to better understand the consequence of human actions on commensal bacteria at the population level. Herein we review the major findings, i.e., puzzle pieces, made with <i>S. pneumoniae</i> and how, over the years, they have come together to shape our understanding of this bacterium's biology and the practice of medicine and modern molecular biology.</p>","PeriodicalId":15107,"journal":{"name":"Journal of Bacteriology","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11332154/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141161777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Repression of <i>Acinetobacter baumannii</i> DNA damage response requires DdrR-assisted binding of UmuDAb dimers to atypical SOS box.","authors":"Belinda Candra, Deborah Cook, Janelle Hare","doi":"10.1128/jb.00432-23","DOIUrl":"10.1128/jb.00432-23","url":null,"abstract":"<p><p>The DNA damage response of the multi-drug-resistant nosocomial pathogen <i>Acinetobacter baumannii</i> possesses multiple features that distinguish it from the commonly used LexA repression system. These include the absence of LexA in this genus, the evolution of a UmuD polymerase manager into the UmuDAb repressor of error-prone polymerases, the use of a corepressor unique to <i>Acinetobacter</i> (DdrR), and an unusually large UmuDAb binding site. We defined cis- and trans-acting factors required for UmuDAb DNA binding and gene repression, and tested whether DdrR directly enhances its DNA binding. We used DNA binding assays to characterize UmuDAb's binding to its proposed operator present upstream of the six co-repressed <i>umuDC</i> or <i>umuC</i> genes. UmuDAb bound tightly and cooperatively to this site with ~10-fold less affinity than LexA. DdrR enhanced the binding of both native and dimerization-deficient UmuDAb forms, but only in greater than equimolar ratios relative to UmuDAb. UmuDAb mutants unable to dimerize or effect gene repression showed impaired DNA binding, and a strain expressing the G124D dimerization mutant could not repress transcription of the UmuDAb-DdrR regulon. Competition electrophoretic mobility shift assays conducted with mutated operator probes showed that, unlike typical SOS boxes, the UmuDAb operator possessed a five-base pair central core whose sequence was more crucial for binding than the flanking palindrome. The presence of only one of the two flanking arms of the palindrome was necessary for UmuDAb binding. Overall, the data supported a model of an operator with two UmuDAb binding sites. The distinct characteristics of UmuDAb and its regulated promoters differ from the typical LexA repression model, demonstrating a novel method of repression.IMPORTANCE<i>Acinetobacter baumannii</i> is a gram-negative bacterium responsible for hospital-acquired infections. Its unique DNA damage response can activate multiple error-prone polymerase genes, allowing it to gain mutations that can increase its virulence and antibiotic resistance. The emergence of infectious strains carrying multiple antibiotic resistance genes, including carbapenem resistance, lends urgency to discovering and developing ways to combat infections resistant to treatment with known antibiotics. Deciphering how the regulators UmuDAb and DdrR repress the error-prone polymerases could lead to developing complementary treatments to halt this mechanism of generating resistance.</p>","PeriodicalId":15107,"journal":{"name":"Journal of Bacteriology","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11332147/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140898230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Asking a question.","authors":"Roberto Kolter","doi":"10.1128/jb.00050-24","DOIUrl":"10.1128/jb.00050-24","url":null,"abstract":"<p><p>While scientific research should be carried out objectively, the choices of questions asked and approaches taken are deeply personal and subjective. I urge individuals to pursue questions they love and to periodically scrutinize the reasons (the philosophies) that drive that love. As a case study, I scrutinize the \"whys\" behind some of the scientific questions I pursued during my career.</p>","PeriodicalId":15107,"journal":{"name":"Journal of Bacteriology","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11332143/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141179670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In memoriam: Pierre Cornelis (1949-2023).","authors":"Jean-Paul Pirnay, Françoise Van Bambeke, Christine Baysse, Miguel Cámara, Sylvie Chevalier, Jean François Collet, Aurélie Crabbé, Jozef Dingemans, Alain Dufour, Linda Eeckhaudt, Alain Filloux, Olivier Lesouhaitier, Qing Wei, Daniel De Vos","doi":"10.1128/jb.00179-24","DOIUrl":"https://doi.org/10.1128/jb.00179-24","url":null,"abstract":"","PeriodicalId":15107,"journal":{"name":"Journal of Bacteriology","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141305968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lamotrigine-mediated rescue of RsgA-deficient Escherichia coli reveals another role of IF2 in ribosome biogenesis","authors":"Sudhir Singh, Jitendra Singh, Umesh Varshney","doi":"10.1128/jb.00119-24","DOIUrl":"https://doi.org/10.1128/jb.00119-24","url":null,"abstract":"RsgA is a late-stage ribosome biogenesis factor. Earlier, infB (IF2) was isolated as a multicopy suppressor of the Escherichia coli ΔrsgA strain. How IF2 rescued the strain growth remained unclear. This study reveals that\u0000(i) the multicopy infB-mediated ...","PeriodicalId":15107,"journal":{"name":"Journal of Bacteriology","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141259663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of Ssc, an <i>N</i>-acetylgalactosamine-containing <i>Staphylococcus aureus</i> surface polysaccharide.","authors":"Mei G Lei, Matthew A Jorgenson, Emily J Robbs, Ian M Black, Stephanie Archer-Hartmann, Sergei Shalygin, Parastoo Azadi, Chia Y Lee","doi":"10.1128/jb.00048-24","DOIUrl":"10.1128/jb.00048-24","url":null,"abstract":"<p><p>Whole genome sequencing has revealed that the genome of <i>Staphylococcus aureus</i> possesses an uncharacterized 5-gene operon (SAOUHSC_00088-00092 in strain 8325 genome) that encodes factors with functions related to polysaccharide biosynthesis and export, indicating the existence of a new extracellular polysaccharide species. We designate this locus as <i>ssc</i> for staphylococcal surface carbohydrate. We found that the <i>ssc</i> genes were weakly expressed and highly repressed by the global regulator MgrA. To characterize Ssc, Ssc was heterologously expressed in <i>Escherichia coli</i> and extracted by heat treatment. Ssc was also conjugated to AcrA from <i>Campylobacter jejuni</i> in <i>E. coli</i> using protein glycan coupling technology (PGCT). Analysis of the heat-extracted Ssc and the purified Ssc-AcrA glycoconjugate by tandem mass spectrometry revealed that Ssc is likely a polymer consisting of <i>N</i>-acetylgalactosamine. We further demonstrated that the expression of the <i>ssc</i> genes in <i>S. aureus</i> affected phage adsorption and susceptibility, suggesting that Ssc is surface-exposed.</p><p><strong>Importance: </strong>Surface polysaccharides play crucial roles in the biology and virulence of bacterial pathogens. <i>Staphylococcus aureus</i> produces four major types of polysaccharides that have been well-characterized. In this study, we identified a new surface polysaccharide containing N-acetylgalactosamine (GalNAc). This marks the first report of GalNAc-containing polysaccharide in <i>S. aureus</i>. Our discovery lays the groundwork for further investigations into the chemical structure, surface location, and role in pathogenesis of this new polysaccharide.</p>","PeriodicalId":15107,"journal":{"name":"Journal of Bacteriology","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11112989/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140850748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In a state of flux: new insight into the transport processes that maintain bacterial metal homeostasis.","authors":"Natalia Kwiatos, Kevin J Waldron","doi":"10.1128/jb.00146-24","DOIUrl":"10.1128/jb.00146-24","url":null,"abstract":"<p><p>A new study by Nies et al. (J Bacteriol 206:e00080-24, 2024, https://doi.org/10.1128/jb.00080-24) provides a rich, quantitative data set of zinc accumulation by cells of <i>Cupriavidus metallidurans</i>, including of mutant bacterial strains lacking import or efflux genes, and comparison of zinc accumulation by cells previously starved of metal with those of zinc-replete cells. The data surprisingly demonstrate the concomitant activity of both active metal import and metal efflux systems. They present a flow equilibrium model to describe zinc homeostasis in bacteria.</p>","PeriodicalId":15107,"journal":{"name":"Journal of Bacteriology","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11112988/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140854895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Functional consequences of modification of the photosystem I/photosystem II ratio in the cyanobacterium Synechocystis sp. PCC 6803","authors":"Vicki MooreWim Vermaas1School of Life Sciences and Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, Arizona, USA, Conrad W. Mullineaux","doi":"10.1128/jb.00454-23","DOIUrl":"https://doi.org/10.1128/jb.00454-23","url":null,"abstract":"Journal of Bacteriology, Ahead of Print. <br/>","PeriodicalId":15107,"journal":{"name":"Journal of Bacteriology","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140827448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}