Molecular Microbiology最新文献_第4页

The Pxp Complex Detoxifies 5-Oxoproline and Promotes the Growth of Clostridioides difficile Pxp复合物解毒5-氧脯氨酸并促进艰难梭菌的生长

IF 3.6 2区生物学

Molecular Microbiology Pub Date : 2025-05-08 DOI: 10.1111/mmi.15373

Cheyenne D. Lee, Arshad Rizvi, Zavier A. Carter, Adrianne N. Edwards, Shonna M. McBride

{"title":"The Pxp Complex Detoxifies 5-Oxoproline and Promotes the Growth of Clostridioides difficile","authors":"Cheyenne D. Lee, Arshad Rizvi, Zavier A. Carter, Adrianne N. Edwards, Shonna M. McBride","doi":"10.1111/mmi.15373","DOIUrl":"https://doi.org/10.1111/mmi.15373","url":null,"abstract":"Clostridioides difficile is an anaerobic enteric pathogen that disseminates in the environment as a dormant spore. For C. difficile and other sporulating bacteria, the initiation of sporulation is a regulated process that prevents spore formation under favorable growth conditions. In Bacillus subtilis, one such mechanism for preventing sporulation is the prokaryotic 5-oxoprolinase, PxpB (KipI), which impedes the activation of the main sporulation kinase. In addition, PxpB functions as part of a complex that detoxifies the intermediate metabolite, 5-oxoproline (OP), a harmful by-product of glutamic acid and its derivatives. In this study, we investigate the orthologous Pxp proteins in C. difficile to determine their roles in the regulation of sporulation and metabolism. Through deletion of the pxpAGBC operon, we show that, unlike in B. subtilis, the Pxp (Kip) proteins have no significant impact on sporulation. However, we found that the pxp operon encodes a functional oxoprolinase that facilitates detoxification of OP. Furthermore, our data demonstrate that PxpAGBC not only detoxifies OP but also allows OP to be used as a nutrient source that supports the growth of C. difficile, thereby facilitating the conversion of a toxic by-product of metabolism into an energy source.","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":"37 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143920960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Luminal Phospholipase D Attacks Bacterial Membranes in Dictyostelium discoideum Phagosomes 腔内磷脂酶D攻击盘状盘牙基钢菌吞噬体中的细菌膜

IF 3.6 2区生物学

Molecular Microbiology Pub Date : 2025-05-04 DOI: 10.1111/mmi.15367

Otmane Lamrabet, Raphael Munoz-Ruiz, Imen Ayadi, Alixia Bourbon, Erwann Pain, Joseph Oddy, Pierre Cosson

引用次数: 0

The Arms Race Between Actinobacillus pleuropneumoniae and Its Genetic Environment: A Comprehensive Analysis of Its Defensome and Mobile Genetic Elements 胸膜肺炎放线杆菌与其遗传环境的军备竞赛：其防御和移动遗传因素的综合分析

IF 3.6 2区生物学

Molecular Microbiology Pub Date : 2025-05-03 DOI: 10.1111/mmi.15374

Giarlã Cunha da Silva, Ciro César Rossi

{"title":"The Arms Race Between Actinobacillus pleuropneumoniae and Its Genetic Environment: A Comprehensive Analysis of Its Defensome and Mobile Genetic Elements","authors":"Giarlã Cunha da Silva, Ciro César Rossi","doi":"10.1111/mmi.15374","DOIUrl":"https://doi.org/10.1111/mmi.15374","url":null,"abstract":"Actinobacillus pleuropneumoniae is the causative agent of pleuropneumonia in swine, a highly contagious and economically significant disease. The genetic variability of A. pleuropneumoniae complicates disease control efforts, as it enables rapid adaptation to various stressors, including antimicrobial treatments. To better understand the molecular mechanisms underlying this adaptability, we investigated the role of the bacterial defensome and its relationship with mobile genetic elements (MGEs), such as prophages, plasmids, and integrative conjugative elements (ICEs). Using bioinformatic tools, we identified a diverse and rich defensome in A. pleuropneumoniae, with an average of 16 different defense systems per strain. We found that CRISPR-Cas systems, along with other defense mechanisms, are actively involved in restricting the entry of foreign genetic material, playing a crucial role in bacterial adaptation. Additionally, we characterized several novel prophages and examined their distribution across different strains, revealing their potential contribution to the bacterium's evolutionary success. Our findings underscore the complex interplay between the bacterium's defense systems and MGEs, shedding light on how A. pleuropneumoniae maintains genetic diversity while also safeguarding itself against external threats. These insights provide a better understanding of the genetic factors that influence the pathogen's adaptability and highlight potential avenues for more effective disease control strategies.","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":"109 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143901813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Identification of EppR, a Second Repressor of Error-Prone DNA Polymerase Genes in Acinetobacter baumannii 鲍曼不动杆菌易出错DNA聚合酶第二抑制基因EppR的鉴定

IF 3.6 2区生物学

Molecular Microbiology Pub Date : 2025-04-19 DOI: 10.1111/mmi.15368

Brian Nguyen, Carly Ching, Ashley MacGuire, Pranav Casula, Connor Newman, Faith Finley, Veronica G. Godoy

{"title":"Identification of EppR, a Second Repressor of Error-Prone DNA Polymerase Genes in Acinetobacter baumannii","authors":"Brian Nguyen, Carly Ching, Ashley MacGuire, Pranav Casula, Connor Newman, Faith Finley, Veronica G. Godoy","doi":"10.1111/mmi.15368","DOIUrl":"https://doi.org/10.1111/mmi.15368","url":null,"abstract":"Acinetobacter baumannii is an opportunistic pathogen causing several infections that are increasingly difficult to treat due to its ability to rapidly gain antibiotic resistances. These resistances can arise due to mutations through the activity of error-prone DNA polymerases, such as DNA polymerase V (DNA Pol V) in response to DNA damage. The regulation of the DNA damage response (DDR) in A. baumannii is not completely understood; the regulation of genes encoding multiple copies of DNA Pol V is not fully characterized. Through genome-wide mutagenesis, we have identified a novel TetR-like family regulator of the umuDC and umuC genes, which we have named Error-prone polymerase regulator (EppR). We have found that EppR represses the expression of the genes encoding DNA Pol V and itself through direct binding to an EppR motif in their promoters. Lastly, we show that EppR also regulates UmuDAb, previously identified as a regulator of genes encoding DNA Pol V. These two gene products are functionally required to ensure regulation of the expression of the two umuDC, the two umuC genes as well as the regulators umuDAb and eppR genes. With these results, we propose a model in which multiple transcription factors regulate the expression of all these genes.","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":"41 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143849527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Protein Homeostasis Impairment Alters Phenotypic Heterogeneity of Biofilm Communities 蛋白质稳态损害改变生物膜群落表型异质性

IF 3.6 2区生物学

Molecular Microbiology Pub Date : 2025-04-17 DOI: 10.1111/mmi.15366

Judith Matavacas, Claes von Wachenfeldt

{"title":"Protein Homeostasis Impairment Alters Phenotypic Heterogeneity of Biofilm Communities","authors":"Judith Matavacas, Claes von Wachenfeldt","doi":"10.1111/mmi.15366","DOIUrl":"https://doi.org/10.1111/mmi.15366","url":null,"abstract":"Biofilms are highly organized, cooperating communities of microorganisms encased in a self-produced extracellular matrix, providing resilience against external stress such as antimicrobial agents and host defenses. A hallmark of biofilms is their phenotypic heterogeneity, which enhances the overall growth and survival of the community. In this study, we demonstrate that removing the dnaK and tig genes encoding the core molecular chaperones DnaK (Hsp70 homolog) and Trigger factor disrupted protein homeostasis in Bacillus subtilis and resulted in the formation of an extremely mucoid biofilm with aberrant architecture, compromised structural integrity, and altered phenotypic heterogeneity. These changes include a large reduction in the motile subpopulation and an overrepresentation of matrix producers and endospores. Overproduction of poly-γ-glutamic acid contributed crucially to the mucoid phenotype and aberrant biofilm architecture. Homeostasis impairment, triggered by elevated temperatures, in wild-type cells led to mucoid and aberrant biofilm phenotypes similar to those observed in strains lacking both dnaK and tig. Our findings show that disruption of protein homeostasis, whether due to the absence of molecular chaperones or because of environmental factors, severely changes biofilm features.","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":"63 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143841627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Converting Blastocrithidia Nonstop, a Trypanosomatid With Non-Canonical Genetic Code, Into a Genetically-Tractable Model 将非规范遗传密码的锥虫Blastocrithidia Nonstop转化为遗传可处理模型

IF 3.6 2区生物学

Molecular Microbiology Pub Date : 2025-04-09 DOI: 10.1111/mmi.15365

Arnau Galan, Natalya Kraeva, Kristína Záhonová, Anzhelika Butenko, Alexei Yu Kostygov, Zdeněk Paris, Jiří Pergner, Claretta Bianchi, Fadel Fakih, Andreu Saura, Julius Lukeš, Vyacheslav Yurchenko

引用次数: 0

PorA of the Type IX Secretion Is a Ligand of the PorXY Two-Component Regulatory System in Porphyromonas gingivalis 牙龈卟啉单胞菌IX型分泌的PorA是PorXY双组分调控系统的配体

IF 3.6 2区生物学

Molecular Microbiology Pub Date : 2025-04-08 DOI: 10.1111/mmi.15363

Momoko Ito, Hideharu Yukitake, Paul D. Veith, Dhana G. Gorasia, Takashi Tominaga, Yuko Sasaki, Eric C. Reynolds, Koji Nakayama, Mariko Naito, Mikio Shoji

{"title":"PorA of the Type IX Secretion Is a Ligand of the PorXY Two-Component Regulatory System in Porphyromonas gingivalis","authors":"Momoko Ito, Hideharu Yukitake, Paul D. Veith, Dhana G. Gorasia, Takashi Tominaga, Yuko Sasaki, Eric C. Reynolds, Koji Nakayama, Mariko Naito, Mikio Shoji","doi":"10.1111/mmi.15363","DOIUrl":"https://doi.org/10.1111/mmi.15363","url":null,"abstract":"Porphyromonas gingivalis is an important bacterium associated with chronic periodontitis. The type IX secretion system (T9SS) in P. gingivalis secretes conserved C-terminal domain (CTD) containing proteins, which are also called T9SS cargo proteins, including gingipain proteinases, to the cell surface and extracellular milieu. We have shown that gene expression of some T9SS component proteins is regulated by a two-component regulatory system, PorX-PorY, an ECF sigma factor, SigP, and a T9SS cargo protein, PorA. As PorA has its own CTD, PorA is mainly localized as an A-LPS-bound form and PorV-bound form on the cell surface. However, it remains unclear how PorA can activate the PorXY-SigP signaling cascade. In this study, our results revealed that the CTD of PorA can activate the PorXY-SigP signaling cascade via interaction with PorY. It is well known that the canonical role of CTD is to act as a secretion signal for T9SS protein export. In here, we propose a novel concept that the CTD of PorA can play a dual role: as a secretion signal directing the secretion of PorA and as a positive regulator of T9SS gene expression by binding to PorY in the periplasm.","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":"1 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143797989","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An Uncharacterized Domain Within the N-Terminal Tail of Histone H3 Regulates the Transcription of FLO1 via Cyc8 组蛋白H3 n端尾部的未知结构域通过Cyc8调控FLO1的转录

IF 3.6 2区生物学

Molecular Microbiology Pub Date : 2025-04-08 DOI: 10.1111/mmi.15362

Ranu Singh, Raghuvir Singh Tomar

{"title":"An Uncharacterized Domain Within the N-Terminal Tail of Histone H3 Regulates the Transcription of FLO1 via Cyc8","authors":"Ranu Singh, Raghuvir Singh Tomar","doi":"10.1111/mmi.15362","DOIUrl":"https://doi.org/10.1111/mmi.15362","url":null,"abstract":"Yeast flocculation relies on cell surface flocculin proteins encoded by the sub-telomeric gene, FLO1. The expression of FLO1 is antagonistically regulated by the Tup1-Cyc8 repressor complex and the Swi-Snf co-activator complexes. The role of hyperacetylated N-terminal amino acid residues of histone H3 and H4 is well established in the transcription of FLO1 and other Tup1-Cyc8 regulated genes. However, sub-domains within the tails of histone H3 and H4 are yet to be identified and the mechanism by which they regulate the FLO1 transcription is completely unexplored. Upon screening of different H3 and H4 N-terminal stretch deletion mutants, we have identified a new region within the N-terminal tail of histone H3, H3Δ(17–24) regulating the transcription of FLO1 and FLO5. This N-terminal truncation mutant showed higher FLO1 and FLO5 expression by 68% and 41% respectively compared to wild-type H3. Further examination showed reduced Cyc8 and nucleosome occupancy in the upstream regulatory region of active flo1 in the H3Δ(17–24) mutant than in H3 wild-type cells. The findings also indicate that Hda1 assists in Cyc8 interaction at the active FLO1 template. Altogether we demonstrate that Tup1-independent interaction of Cyc8 with the active FLO1 gene acts as a transcription limiting factor and that the histone H3 N-terminal 17–24 stretch is essential for this interaction. In the absence of the 17–24 stretch, the Cyc8 restrictive effect is altered, resulting in over-expression of FLO1.","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":"4 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143798390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Power Duo: How the Interplay Between Nucleoid-Associated Proteins and Small Noncoding RNAs Orchestrates the Cellular Regulatory Symphony 权力二人组：核相关蛋白和小非编码rna之间的相互作用如何协调细胞调节交响乐

IF 3.6 2区生物学

Molecular Microbiology Pub Date : 2025-04-05 DOI: 10.1111/mmi.15359

Sara Moutacharrif, Feth El Zahar Haichar, Sam Meyer, Cecile Ribot, Sylvie Reverchon, William Nasser, Florence Hommais

{"title":"The Power Duo: How the Interplay Between Nucleoid-Associated Proteins and Small Noncoding RNAs Orchestrates the Cellular Regulatory Symphony","authors":"Sara Moutacharrif, Feth El Zahar Haichar, Sam Meyer, Cecile Ribot, Sylvie Reverchon, William Nasser, Florence Hommais","doi":"10.1111/mmi.15359","DOIUrl":"https://doi.org/10.1111/mmi.15359","url":null,"abstract":"In bacteria, the regulation of gene expression involves complex networks that integrate both transcriptional and posttranscriptional mechanisms. At the transcriptional level, nucleoid-associated proteins (NAPs) such as H-NS, HU, Lrp, IHF, Fis and Hfq are key players as they not only compact bacterial DNA but also regulate transcription. Small noncoding RNAs (sRNAs), on the other hand, are known to affect bacterial gene expression posttranscriptionally by base pairing with the target mRNA, but they can also be involved in nucleoid condensation. Interestingly, certain NAPs also influence the function of sRNAs and, conversely, sRNAs themselves can modulate the activity of NAPs, creating a complex bidirectional regulatory network. Here, we summarise the current knowledge of the major NAPs, focusing on the specific role of Hfq. Examples of the regulation of NAPs by sRNAs, the regulation of sRNAs by NAPs and the role of sRNAs in nucleoid structuring are also discussed. This review focuses on the cross-talk between NAPs and sRNAs in an attempt to understand how this interplay works to orchestrate the functioning of the cell.","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":"20 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143784728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Cellodextrin Metabolism and Phosphotransferase System-Catalyzed Uptake in Enterococcus faecalis. 粪肠球菌纤维素糊精代谢和磷酸转移酶系统催化的摄取。

IF 2.6 2区生物学

Molecular Microbiology Pub Date : 2025-04-01 Epub Date: 2025-02-13 DOI: 10.1111/mmi.15346

Victor Combret, Isabelle Rincé, Ronan Cochelin, Florie Desriac, Cécile Muller, Diane Soussan, Axel Hartke, Josef Deutscher, Nicolas Sauvageot

{"title":"Cellodextrin Metabolism and Phosphotransferase System-Catalyzed Uptake in Enterococcus faecalis.","authors":"Victor Combret, Isabelle Rincé, Ronan Cochelin, Florie Desriac, Cécile Muller, Diane Soussan, Axel Hartke, Josef Deutscher, Nicolas Sauvageot","doi":"10.1111/mmi.15346","DOIUrl":"10.1111/mmi.15346","url":null,"abstract":"Two PTS transporters involved in the uptake of cellobiose and short cellooligosaccharides were identified in Enterococcus faecalis. Genes coding for the different EII proteins are found in a locus composed of three operonic structures expressing two distinct EIIC (CelC1 and CelC2), two identical EIIB (CelB1 and CelB2) and a unique EIIA (CelA1). The EIIA plays a central role in β-glucoside uptake because it is required not only for β-homodiholosides but also for the diheteroside N-acetylglucosamine-L-asparagine. Depending on their size, cellooligosaccharides are preferably transported either by CelC1 (di-saccharides) or by CelC2 (4 glycosidic residues and more), with tri-saccharides being taken up by both EIIC transporters. Moreover, CelA1B2C2 require CelGHI to be functional, three small proteins, the function of which remains unknown. CelA1B1C1 is the main but not exclusive transporter of cellobiose and chitobiose. It is involved in the transport of other β-glucodisaccharides, such as laminaribiose and sophorose. This PTS can be complemented by other transporters highlighting the existence of a network for β-glucoside uptake. This locus is under the control of CelR, a LevR-like transcription activator.","PeriodicalId":19006,"journal":{"name":"Molecular Microbiology","volume":" ","pages":"378-391"},"PeriodicalIF":2.6,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11976118/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143414629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0