is a pathogen that causes disease in millions of people every year by colonizing the small intestine and then secreting the potent cholera toxin. How the pathogen overcomes the colonization barrier created by the host's natural microbiota is, however, still not well understood. In this context, the type VI secretion system (T6SS) has gained considerable attention given its ability to mediate interbacterial killing.
View Article and Find Full Text PDFStress granules (SGs) are non-membranous organelles facilitating stress responses and linking the pathology of age-related diseases. In a genome-wide imaging-based phenomic screen, we identify Pab1 co-localizing proteins under 2-deoxy-D-glucose (2-DG) induced stress in Saccharomyces cerevisiae. We find that deletion of one of the Pab1 co-localizing proteins, Lsm7, leads to a significant decrease in SG formation.
View Article and Find Full Text PDFBackground: Intestinal failure (IF) is defined as an ultrarare disease, with an estimated prevalence of ∼25,000 cases in the US. There is a suspicion of disparities in outcomes in IF care, likely related to widespread lack of expertise. The Extension for Community Healthcare Outcomes (ECHO) model originally described by Dr Sanjeev Arora has been used to disseminate knowledge and best practices in many chronic diseases to improve outcomes.
View Article and Find Full Text PDFPatients with intestinal failure (IF) often require home parenteral and/or enteral nutrition (HPEN). There are many complications associated with both IF and the use of HPEN, including infection and intolerance. Psychosocial effects, such as depression, isolation, fatigue, anxiety, financial stress, are also associated with IF and HPEN and can be difficult to address.
View Article and Find Full Text PDFBacteria of the genus Vibrio are common members of aquatic environments where they compete with other prokaryotes and defend themselves against grazing predators. A macromolecular protein complex called the type VI secretion system (T6SS) is used for both purposes. Previous research showed that the sole T6SS of the human pathogen V.
View Article and Find Full Text PDFType VI secretion systems (T6SSs) are nanomachines used for interbacterial killing and intoxication of eukaryotes. Although Vibrio cholerae is a model organism for structural studies on T6SSs, the underlying regulatory network is less understood. A recent study showed that the T6SS is part of the natural competence regulon in V.
View Article and Find Full Text PDFThe human pathogen Vibrio cholerae is an autochthonous inhabitant of aquatic environments where it often interacts with zooplankton and their chitinous molts. Chitin induces natural competence for transformation in V. cholerae, a key mode of horizontal gene transfer (HGT).
View Article and Find Full Text PDFNatural competence for transformation is a common mode of horizontal gene transfer and contributes to bacterial evolution. Transformation occurs through the uptake of external DNA and its integration into the genome. Here we show that the type VI secretion system (T6SS), which serves as a predatory killing device, is part of the competence regulon in the naturally transformable pathogen Vibrio cholerae.
View Article and Find Full Text PDFNatural competence for transformation is a developmental program that allows certain bacteria to take up free extracellular DNA from the environment and integrate this DNA into their genome. Thereby, natural transformation acts as mode of horizontal gene transfer and impacts bacterial evolution. The number of genes induced upon competence induction varies significantly between organisms.
View Article and Find Full Text PDFThe general stress response of alphaproteobacteria is regulated by a partner-switching mechanism that involves the alternative sigma factor σ(EcfG), the anti-sigma factor NepR and the anti-sigma factor antagonist PhyR. To address the question of how the PhyR-NepR-σ(EcfG) cascade is activated and modulated in Methylobacterium extorquens, a forward genetic screen was applied. The screen identified the single-domain response regulator Mext_0407 as a novel regulatory element in the general stress response of M.
View Article and Find Full Text PDFThe general stress response in Alphaproteobacteria was recently described to depend on the alternative sigma factor σ(EcfG), whose activity is regulated by its anti-sigma factor NepR. The response regulator PhyR, in turn, regulates NepR activity in a partner-switching mechanism according to which phosphorylation of PhyR triggers sequestration of NepR by the sigma factor-like effector domain of PhyR. Although genes encoding predicted histidine kinases can often be found associated with phyR, little is known about their role in modulation of PhyR phosphorylation status.
View Article and Find Full Text PDFParenteral and enteral nutrition (PEN) are life-sustaining therapies that can be administered in the home. They are also complex therapies, with many facets about which patients and caregivers must learn. Once home on PEN, the patient assumes much of the responsibility for day-to-day care.
View Article and Find Full Text PDFThe needle length of the Yersinia spp. injectisome is determined by Yop secretion protein P (YscP), an early substrate of the injectisome itself. There is a linear correlation between the length of YscP and the length of the needle, suggesting that YscP acts as a molecular ruler.
View Article and Find Full Text PDFThis study examined adolescent risk factors for late-onset cigarette smoking among African American males. Data came from the Pittsburgh Youth Study, a longitudinal study of young men followed from age 13 to age 25. Individuals who began smoking at age 17 or older were compared with those who began smoking by age 16 and with those who never smoked in terms of risk factors measured in middle (at age 16) and late adolescence (from age 17 to 19).
View Article and Find Full Text PDFThe hepadnaviral polymerase (P) functions in a complex with viral nucleic acids and cellular chaperones. To begin to identify contacts between P and its partners, we assessed the exposure of the epitopes of six monoclonal antibodies (MAbs) to the terminal protein domain of the duck hepatitis B virus P protein in a partially denaturing buffer (RIPA) and a physiological buffer (IPP150). All MAbs immunoprecipitated in vitro translated P well in RIPA, but three immunoprecipitated P poorly in IPP150.
View Article and Find Full Text PDFStudies of the broader autism phenotype, and of subtle changes in autism symptoms over time, have been compromised by a lack of established quantitative assessment tools. The Social Responsiveness Scale (SRS-formerly known as the Social Reciprocity Scale) is a new instrument that can be completed by parents and/or teachers in 15-20 minutes. We compared the SRS with the Autism Diagnostic Interview-Revised (ADI-R) in 61 child psychiatric patients.
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