Contributions to microbiology最新文献_第2页

Bacterial sensing of antimicrobial peptides. 抗菌肽的细菌感应。

Contributions to microbiology Pub Date : 2009-01-01 Epub Date: 2009-06-02 DOI: 10.1159/000219377

Michael Otto

{"title":"Bacterial sensing of antimicrobial peptides.","authors":"Michael Otto","doi":"10.1159/000219377","DOIUrl":"https://doi.org/10.1159/000219377","url":null,"abstract":"Antimicrobial peptides (AMPs) form a crucial part of human innate host defense, especially in neutrophil phagosomes and on epithelial surfaces. Bacteria have a variety of efficient resistance mechanisms to human AMPs, such as efflux pumps, secreted proteases, and alterations of the bacterial cell surface that are aimed to minimize attraction of the typically cationic AMPs. In addition, bacteria have specific sensors that activate AMP resistance mechanisms when AMPs are present. The prototypical Gram-negative PhoP/PhoQ and the Gram-positive Aps AMP-sensing systems were first described and investigated in Salmonella typhimurium and Staphylococcus epidermidis, respectively. Both include a classical bacterial two-component sensor/regulator system, but show many structural, mechanistic, and functional differences. The PhoP/PhoQ regulon controls a variety of genes not necessarily limited to AMP resistance mechanisms, but apparently aimed to combat innate host defense on a broad scale. In contrast, the staphylococcal Aps system predominantly upregulates AMP resistance mechanisms, namely the D-alanylation of teichoic acids, inclusion of lysyl-phosphati-dylglycerol in the cytoplasmic membrane, and expression of the putative VraFG AMP efflux pump. Notably, both systems are crucial for virulence and represent possible targets for antimicrobial therapy.","PeriodicalId":79855,"journal":{"name":"Contributions to microbiology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000219377","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28218864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 99

Bacterial PEP-dependent carbohydrate: phosphotransferase systems couple sensing and global control mechanisms. 细菌pep依赖碳水化合物:磷酸转移酶系统偶联传感和全局控制机制。

Contributions to microbiology Pub Date : 2009-01-01 Epub Date: 2009-06-02 DOI: 10.1159/000219373

Joseph W Lengeler, Knut Jahreis

{"title":"Bacterial PEP-dependent carbohydrate: phosphotransferase systems couple sensing and global control mechanisms.","authors":"Joseph W Lengeler, Knut Jahreis","doi":"10.1159/000219373","DOIUrl":"https://doi.org/10.1159/000219373","url":null,"abstract":"The PEP-dependent carbohydrate:phosphotransferase systems (PTSs) of enteric bacteria constitute a complex sensory system which involves as its central element a PEP-dependent His-protein kinase (Enzyme I). As a unit, the PTS comprises up to 20 different transporters per cell which correspond to its chemoreceptors for PTS carbohydrates, and several targeting subunits, which include in the low [G+C] Gram-positive bacteria an ancillary Ser/Thr-protein kinase. The PTS senses the presence of carbohydrates, in particular glucose, in the medium and the energy state of the cell, in the form of either the intracellular PEP-to-pyruvate ratio or the D-fructose-bisphosphate levels. This information is subsequently communicated to cellular targets, in particular those involved in the chemotactic response of the cell towards PTS carbohydrates, and in sensing glucose in the medium, using cAMP and several targeting subunits as intermediates. Peptide targeting subunits ensure the fast, transient, and yet accurate communication of the PTS with its more than hundred different targets, avoiding at the same time unwanted cross-talk. Many elements of this sensory system are simultaneously elements of specific and global regulatory networks. Thus, the PTS controls, besides the immediate (in the ms to s range) chemotactic responses, the activity of the various carbohydrate transporters and enzymes involved in carbon and energy metabolism through inducer exclusion, and in a delayed response (in the min to h range) the synthesis of these transporters and catabolic enzymes through catabolite repression. Indirect consequences of this program are phenomena related to cell surface rearrangements, which include flagella synthesis, as well as memory, adaptation, and learning effects. The analogy between the PTS and other prokaryotic systems, and more complex sensory systems from eukaryotic organisms which share elements with regulatory systems is obvious.","PeriodicalId":79855,"journal":{"name":"Contributions to microbiology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000219373","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28219621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 93

Prevailing concepts of c-di-GMP signaling. c-di-GMP信号传导的流行概念。

Contributions to microbiology Pub Date : 2009-01-01 Epub Date: 2009-06-02 DOI: 10.1159/000219379

Ute Römling, Roger Simm

引用次数: 68

Magnetosomes and magneto-aerotaxis. 磁小体和磁需氧性。

Contributions to microbiology Pub Date : 2009-01-01 Epub Date: 2009-06-02 DOI: 10.1159/000219380

Richard B Frankel, Dennis A Bazylinski

引用次数: 28

Engineering bacterial signals and sensors. 工程细菌信号和传感器。

Contributions to microbiology Pub Date : 2009-01-01 Epub Date: 2009-06-02 DOI: 10.1159/000219381

Howard Salis, Alvin Tamsir, Christopher Voigt

引用次数: 52

Correlations between carbon metabolism and virulence in bacteria. 细菌中碳代谢与毒力的关系。

Contributions to microbiology Pub Date : 2009-01-01 Epub Date: 2009-06-02 DOI: 10.1159/000219374

Sandrine Poncet, Eliane Milohanic, Alain Mazé, Jamila Nait Abdallah, Francine Aké, Mireille Larribe, Ala-Eddine Deghmane, Muhamed-Kheir Taha, Marie Dozot, Xavier De Bolle, Jean Jacques Letesson, Josef Deutscher

{"title":"Correlations between carbon metabolism and virulence in bacteria.","authors":"Sandrine Poncet, Eliane Milohanic, Alain Mazé, Jamila Nait Abdallah, Francine Aké, Mireille Larribe, Ala-Eddine Deghmane, Muhamed-Kheir Taha, Marie Dozot, Xavier De Bolle, Jean Jacques Letesson, Josef Deutscher","doi":"10.1159/000219374","DOIUrl":"https://doi.org/10.1159/000219374","url":null,"abstract":"Bacteria have developed several mechanisms which allow the preferred utilization of the most efficiently metabolizable carbohydrates when these organisms are exposed to a mixture of carbon sources. Interestingly, the same or similar mechanisms are used by some pathogens to control various steps of their infection process. The efficient metabolism of a carbon source might serve as signal for proper fitness. Alternatively, the presence of a specific carbon source might indicate to bacterial cells that they thrive in infection-related organs, tissues or cells and that specific virulence genes should be turned on or switched off. Frequently, virulence gene regulators are affected by changes in carbon source availability. For example, expression of the gene encoding the Streptococcus pyogenes virulence regulator Mga is controlled by the classical carbon catabolite repression (CCR) mechanism operative in Firmicutes. The activity of PrfA, the major virulence regulator in Listeria monocytogenes, seems to be controlled by the phosphorylation state of phosphotransferase system(PTS) components. In Vibrio cholerae synthesis of HapR, which regulates the expression of genes required for motility, is controlled via the Crp/cAMP CCR mechanism, whereas synthesis of Salmonella enterica HilE, which represses genes in a pathogenicity island, is regulated by the carbohydrate-responsive, PTS-controlled Mlc.","PeriodicalId":79855,"journal":{"name":"Contributions to microbiology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000219374","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28219622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 129

Contributions to microbiology. Bacterial sensing and signaling. Foreword. 对微生物学的贡献细菌感应和信号。前言。

Contributions to microbiology Pub Date : 2009-01-01 DOI: 10.1159/isbn.978-3-8055-9133-1

Mattias Collin, Raymond Schuch

引用次数: 14

Autoinducer-2-based chemical communication in bacteria: complexities of interspecies signaling. 细菌中基于自诱导剂2的化学通讯:种间信号的复杂性。

Contributions to microbiology Pub Date : 2009-01-01 Epub Date: 2009-06-02 DOI: 10.1159/000219371

Michael J Federle

{"title":"Autoinducer-2-based chemical communication in bacteria: complexities of interspecies signaling.","authors":"Michael J Federle","doi":"10.1159/000219371","DOIUrl":"https://doi.org/10.1159/000219371","url":null,"abstract":"Cell-cell communication in bacteria, called quorum sensing, relies on production, release, and detection of signaling molecules, termed autoinducers. Communication enables populations of cells to synchronize gene expression and therefore behave as a group in a manner akin to cells in multicellular organisms. Most quorum-sensing systems allow communication within an individual species of bacteria. However, one autoinducer, called AI-2, is produced and recognized by many different bacterial species, indicating that some bacteria communicate across species boundaries. Current studies are aimed at discovering the role that AI-2 plays in gene regulation. Differential gene expression in response to AI-2 may cause bacterial behavioral changes, such as biofilm formation or transition to a pathogenic state. Interestingly, multiple mechanisms to detect AI-2 exist. These differences likely reflect variations in the role that AI-2 plays for different bacteria. Additionally, structural analyses of the AI-2 receptor in V. harveyi have provided insight into bacterial trans-membrane signal transduction. A further understanding of bacterial quorum-sensing processes may facilitate development of new technologies aimed at interfering with bacterial communication and virulence.","PeriodicalId":79855,"journal":{"name":"Contributions to microbiology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000219371","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28219619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 116

Stand-alone response regulators controlling global virulence networks in streptococcus pyogenes. 控制化脓性链球菌全球毒力网络的独立反应调节器。

Contributions to microbiology Pub Date : 2009-01-01 Epub Date: 2009-06-02 DOI: 10.1159/000219375

Kevin S McIver

引用次数: 59

RNA thermosensors in bacterial pathogens. 细菌病原体中的RNA热传感器。

Contributions to microbiology Pub Date : 2009-01-01 Epub Date: 2009-06-02 DOI: 10.1159/000219378

Jörgen Johansson

引用次数: 20