ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • Pathogens & Pathogenicity  (51)
  • Oxford University Press  (51)
  • American Physical Society
  • 1
    facet.materialart.
    Unbekannt
    Comparative proteomic analysis unravels a role for EsrB in the regulation of reactive oxygen species stress responses in Edwardsiella piscicida (2017)
    Oxford University Press
    Details
    Publikationsdatum: 2017-01-13
    Beschreibung: As a leading pathogen, Edwardsiella piscicida can cause hemorrhagic septicemia in fish and gastro-intestinal infections in humans. The two-component regulatory system EsrA-EsrB plays essential roles in pathogenesis through the type III and type VI secretion systems, and hemolysin production in E. piscicida . It is unclear whether other virulence- or stress response-associated genes are regulated by EsrA-EsrB. In this study, the proteomes of wild-type E. piscicida EIB202 and esrB mutant strains were compared to reveal EsrB regulon components after growth in Luria–Bertani broth (LB). Overall, the expression levels of nine genes exhibited significant changes, and five of them required the presence of EsrB, while others exhibited higher levels in the esrB mutant. The diverse functions of these proteins were identified, including amino acid metabolism, oxidative stress defense and energy production. Interestingly, superoxidase dismutase and thiol peroxidase were the most significantly down-regulated by EsrB. Furthermore, other reported reactive oxygen species (ROS) resistance-related genes were also down-regulated by EsrB as revealed by quantitative real-time. Compared with the wild-type and the complement strain esrB + , esrB displayed a significantly enhanced ROS resistance. These results demonstrated that EsrB plays important roles in the ROS resistance pathway in E. piscicida grown in LB conditions.
    Schlagwort(e): Pathogens & Pathogenicity
    Print ISSN: 0378-1097
    Digitale ISSN: 1574-6968
    Thema: Biologie
    Publiziert von Oxford University Press
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    AKTUELLE ARTIKEL
  • 2
    facet.materialart.
    Unbekannt
    Importance of fumarate and nitrate reduction regulatory protein for intestinal proliferation of Vibrio vulnificus (2017)
    Oxford University Press
    Details
    Publikationsdatum: 2017-01-13
    Beschreibung: The sepsis caused by Vibrio vulnificus is characterized by an average incubation period of 26 h and a high mortality rate exceeding 50%. The fast growth and dissemination of V. vulnificus in vivo lead to poor clinical outcomes in patients. Therefore, elucidation of the proliferation mechanisms of this organism in vivo may lead to the development of an effective therapeutic strategy. In this study, we focused on the low oxygen concentration in the intestinal milieu because of its drastic difference from that in air. Fumarate and nitrate reduction regulatory protein (FNR) is known to be a global transcriptional regulator for adaptation to anaerobic conditions in various bacteria. We generated a strain of V. vulnificus in which the fnr gene was replaced with an erythromycin resistance gene ( fnr :: erm mutant). When the fnr :: erm mutant was tested in a growth competition assay against the wild-type (WT) in vivo , the competitive index of fnr :: erm mutant to WT in the intestinal loop and liver was 0.378 ± 0.192 (mean ± SD) and 0.243 ± 0.123, respectively. These data suggested that FNR is important for the proliferation of V. vulnificus in the intestine to achieve a critical mass to be able to invade the systemic circulation.
    Schlagwort(e): Pathogens & Pathogenicity
    Print ISSN: 0378-1097
    Digitale ISSN: 1574-6968
    Thema: Biologie
    Publiziert von Oxford University Press
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    AKTUELLE ARTIKEL
  • 3
    facet.materialart.
    Unbekannt
    Cag-delta (Cag3) protein from the Helicobacter pylori 26695 cag type IV secretion system forms ring-like supramolecular assemblies (2017)
    Oxford University Press
    Details
    Publikationsdatum: 2017-01-08
    Beschreibung: Helicobacter pylori is an important cause of gastric pathologies and persistent infection can lead to stomach cancer. Virulent H. pylori strains encode a type IV secretion system responsible for translocation of the oncogenic CagA protein into cells of the gastric mucosa. Gene HP0522 encodes the essential component Cag (Cag3), and we show by gel filtration and cross-linking that purified Cag forms high molecular mass complexes. In contrast, its interaction partner CagT is mostly monomeric, but co-fractionates after gel filtration. Analysis by transmission electron microscopy revealed that purified Cag complexes can self-assemble ring-like structures. Cag-overexpressing Escherichia coli exhibits membrane-associated circular profiles in regions of the cell envelope with intense immunogold labelling with a Cag-specific antiserum. Our results suggest that Cag has the capacity to form macromolecular structures contributing to the assembly of the type IV secretion system.
    Schlagwort(e): Pathogens & Pathogenicity
    Print ISSN: 0378-1097
    Digitale ISSN: 1574-6968
    Thema: Biologie
    Publiziert von Oxford University Press
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    AKTUELLE ARTIKEL
  • 4
    facet.materialart.
    Unbekannt
    Characterization of the Cag pathogenicity island in Helicobacter pylori from naturally infected rhesus macaques (2016)
    Oxford University Press
    Details
    Publikationsdatum: 2016-12-29
    Beschreibung: Helicobacter pylori commonly infects the epithelial layer of the human stomach and in some individuals causes peptic ulcers, gastric adenocarcinoma or gastric lymphoma. Helicobacter pylori is a genetically diverse species, and the most important bacterial virulence factor that increases the risk of developing disease, versus asymptomatic colonization, is the cytotoxin associated gene pathogenicity island ( cag PAI). Socially housed rhesus macaques are often naturally infected with H. pylori similar to that which colonizes humans, but little is known about the cag PAI. Here we show that H. pylori strains isolated from naturally infected rhesus macaques have a cag PAI very similar to that found in human clinical isolates, and like human isolates, it encodes a functional type IV secretion system. These results provide further support for the relevance of rhesus macaques as a valid experimental model for H. pylori infection in humans.
    Schlagwort(e): Pathogens & Pathogenicity
    Print ISSN: 0378-1097
    Digitale ISSN: 1574-6968
    Thema: Biologie
    Publiziert von Oxford University Press
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    AKTUELLE ARTIKEL
  • 5
    facet.materialart.
    Unbekannt
    Molecular variability and genetic relationship among Brazilian strains of the sugarcane smut fungus (2016)
    Oxford University Press
    Details
    Publikationsdatum: 2016-12-29
    Beschreibung: Sporisorium scitamineum is the fungus that causes sugarcane smut disease. Despite of the importance of sugarcane for Brazilian agribusiness and the persistence of the pathogen in most cropping areas, genetic variation studies are still missing for Brazilian isolates. In this study, sets of isolates were analyzed using two molecular markers (AFLP and telRFLP) and ITS sequencing. Twenty-two whips were collected from symptomatic plants in cultivated sugarcane fields of Brazil. A total of 41 haploid strains of compatible mating types were selected from individual teliospores and used for molecular genetic analyses. telRFLP and ITS analyses were expanded to six Argentine isolates, where the sugarcane smut was first recorded in America. Genetic relationship among strains suggests the human-mediated dispersal of S. scitamineum within the Brazilian territory and between the two neighboring countries. Two genetically distinct groups were defined by the combined analysis of AFLP and telRFLP. The opposite mating-type strains derived from single teliospores were clustered together into these main groups, but had not always identical haplotypes. telRFLP markers analyzed over two generations of selfing and controlled outcrossing confirmed the potential for emergence of new variants and occurrence of recombination, which are relevant events for evolution of virulence and environmental adaptation.
    Schlagwort(e): Pathogens & Pathogenicity
    Print ISSN: 0378-1097
    Digitale ISSN: 1574-6968
    Thema: Biologie
    Publiziert von Oxford University Press
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    AKTUELLE ARTIKEL
  • 6
    facet.materialart.
    Unbekannt
    A predicted cation transporter protein, BPSS1228, is involved in intracellular behaviour of Burkholderia pseudomallei in a human lung epithelial cell line (A549) (2016)
    Oxford University Press
    Details
    Publikationsdatum: 2016-12-23
    Beschreibung: Burkholderia pseudomallei causes melioidosis, a potentially fatal infectious disease in tropical and subtropical countries worldwide. The intracellular behaviour of this pathogen in host cells has been reported to impact the severity of melioidosis, including the development of septicaemia, a consequence of pneumonia melioidosis. We previously identified a predicted cation transporter protein, BPSS1228, that participates in the transitional stage of this intracellular pathogen. For further analysis, in this study B. pseudomallei bpss1228 mutant and complemented strains were constructed and bacterial infectivity on human lung epithelial cells, A549, investigated in vitro . Burkholderia pseudomallei bpss1228 mutant showed impaired bacterial adhesion and invasion into A549 cells compared with wild-type strain, while the deficient phenotypes were restored to wild-type levels by the complemented strain. Additionally, the inactivation of bpss1228 in the mutant strain affected flagella-based swimming on a semi-solid surface and resistance to acid stresses simulating intracellular environments. These observations of BPSS1228 relating to B. pseudomallei infection strategies shed a new light on its association with intracellular B. pseudomallei during the interaction with host cells.
    Schlagwort(e): Pathogens & Pathogenicity
    Print ISSN: 0378-1097
    Digitale ISSN: 1574-6968
    Thema: Biologie
    Publiziert von Oxford University Press
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    AKTUELLE ARTIKEL
  • 7
    facet.materialart.
    Unbekannt
    Theoretical and experimental evidence for eliminating persister bacteria by manipulating killing timing (2016)
    Oxford University Press
    Details
    Publikationsdatum: 2016-12-23
    Beschreibung: Formation of a transient sub-population of bacteria, referred to as persisters, is one of the most important and least understood mechanisms that bacteria employ to evade elimination. Persister cells appear to be slow-growing bacteria that are broadly protected from a wide range of antibiotics. Using both theoretical and experimental methods, we show that alternating the application and withdrawal of antibiotics can be an effective treatment—as long as the timing of the protocol is estimated with precision. More specifically, we demonstrate that timing the alternating treatment based on theoretical predictions is confirmed using experimental observations. These results support a large class of theoretical studies that show that, even without complete understanding of the biological mechanisms, these models can provide insight into properties of the system.
    Schlagwort(e): Pathogens & Pathogenicity
    Print ISSN: 0378-1097
    Digitale ISSN: 1574-6968
    Thema: Biologie
    Publiziert von Oxford University Press
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    AKTUELLE ARTIKEL
  • 8
    facet.materialart.
    Unbekannt
    N-(3-oxo-hexanoyl)-homoserine lactone has a critical contribution to the quorum-sensing-dependent regulation in phytopathogen Pseudomonas syringae pv. tabaci 11528 (2016)
    Oxford University Press
    Details
    Publikationsdatum: 2016-12-23
    Beschreibung: The phytopathogen Pseudomonas syringae pv. tabaci 11528 ( P. syringae 11528), causing wild-fire disease in soybean and tobacco plants, processes PsyI-PsyR quorum-sensing (QS) system, in which PsyI is the N -(3-oxo-hexanoyl)-homoserine lactone (3OC6-HSL) synthase. In comparison to P. syringae 11528 AHL-deficient mutant, 845 3OC6-HSL-dependent genes were identified using RNA sequencing (RNA-seq) in the AHL-deficient mutant grown with exogenous 3OC6-HSL in the transition from the exponential to the stationary phase, and many of them were associated with virulence, which were negatively regulated. The gene ontology and KEGG pathway enrichment analysis of those genes presented that the most pronounced regulation was involved in bacterial motility. Moreover, similar expression profiles of genes during growth phases were observed in both the wild type and the AHL-deficient mutant with exogenous 3OC6-HSL compared with the AHL-deficient mutant. These findings imply that 3OC6-HSL has a critical contribution to the QS-dependent regulation on gene expression, and 3OC6-HSL-dependent regulation may play a significant role in plant infection.
    Schlagwort(e): Pathogens & Pathogenicity
    Print ISSN: 0378-1097
    Digitale ISSN: 1574-6968
    Thema: Biologie
    Publiziert von Oxford University Press
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    AKTUELLE ARTIKEL
  • 9
    facet.materialart.
    Unbekannt
    Arf6 controls endocytosis and polarity during asexual development of Magnaporthe oryzae (2016)
    Oxford University Press
    Details
    Publikationsdatum: 2016-12-16
    Beschreibung: Asexual development of phytopathogenic fungi such as Magnaporthe oryzae involves morphological changes that require spatiotemporal regulation of polarized growth. ADP-ribosylation factor 6 (Arf6) is a small GTPase known to regulate membrane trafficking and organization of the actin cytoskeleton at the cell surface, and consequently has an impact on cell morphology and polarity. In this study, we have functionally characterized the Arf6 homolog in M. oryzae , showing that arf6 exhibits hyperbranching at hyphal tips and morphologically abnormal conidia as a result of defective polarized growth. arf6 hyphae are also defective in endocytosis as evidenced by a significant delay of FM4-64 uptake. Most arf6 conidia display reduced conidial length, and have defects in conidial septum formation and nuclear distribution. Furthermore, arf6 conidia show a disorganized actin cytoskeleton with random distribution of actin patches at the cell cortex and reduced accumulation of tropomyosin. Arf6-GFP is found to concentrate at the septum area and possibly in endocytic vesicles. Taken together, our data indicate that Arf6 plays an essential role in endocytosis and polarity establishment during asexual development of M. oryzae.
    Schlagwort(e): Pathogens & Pathogenicity
    Print ISSN: 0378-1097
    Digitale ISSN: 1574-6968
    Thema: Biologie
    Publiziert von Oxford University Press
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    AKTUELLE ARTIKEL
  • 10
    facet.materialart.
    Unbekannt
    Effect of kpsM on the virulence of porcine extraintestinal pathogenic Escherichia coli (2016)
    Oxford University Press
    Details
    Publikationsdatum: 2016-11-17
    Beschreibung: In recent years, extraintestinal pathogenic Escherichia coli (ExPEC) has been found to pose a great threat to human and animal health, but its pathogenic mechanism is not fully understood yet. Capsular polysaccharide, an essential virulence factor in these bacteria, can damage the host immune system, and kpsM is a member of the gene cluster responsible for capsular polysaccharide synthesis. In this study, whole sequence alignment of the virulent strain PCN033 and the attenuated strain PCN061 revealed that kpsM exists in PCN033 but not in PCN061. To determine its function and biological characteristics, we deleted kpsM from PCN033 by homologous recombination. The results of adhesion assays, phagocytosis assays and serum bactericidal assays together with the results of colonization assays in mice indicate that the deletion of kpsM decreases the virulence of porcine ExPEC. Our findings about the biological characteristics of kpsM help to elucidate the complex pathogenic mechanism of ExPEC.
    Schlagwort(e): Pathogens & Pathogenicity
    Print ISSN: 0378-1097
    Digitale ISSN: 1574-6968
    Thema: Biologie
    Publiziert von Oxford University Press
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    AKTUELLE ARTIKEL
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...