Project description:Identification of the specific WalR (YycF) binding regions on the B. subtilis chromosome during exponential and phosphate starvation growth phases. The data serves to extend the WalRK regulon in Bacillus subtilis and its role in cell wall metabolism, as well as implying a role in several other cellular processes.
Project description:Transcriptome comparison of Bacillus subtilis Natto under sliding permissive (0.7% agar) and restrictive (1.5% agar or spo0A mutant strain) conditions.
Project description:Identification of the specific WalR (YycF) binding regions on the B. subtilis chromosome during exponential and phosphate starvation growth phases. The data serves to extend the WalRK regulon in Bacillus subtilis and its role in cell wall metabolism, as well as implying a role in several other cellular processes. For each sample analyzed in this study three biological replicates were performed. Three different samples were taken from a strain expressing the WalR-SPA protein as well as from wild-type (168) without a tagged WalR. Samples were taken from exponentially growing cells in low phosphate medium (LPDM) as well as from phosphate-limited cells (T2). Each sample compares ChIP DNA vs. Total DNA from the same cells.
Project description:Human Peptidoglycan Recognition Proteins (PGRPs) kill bacteria, likely by over-activating stress responses in bacteria. To gain insight into the mechanism of PGRP killing of Bacillus subtilis and bacterial defense against PGRP killing, gene expression in B. subtilis treated with a control protein (bovine serum albumin, BSA), human recombinant PGRP (PGLYRP4), gentamicin (aminoglycoside antibiotic), and CCCP (membrane potential decoupler) were compared. Each treatment induced unique and somewhat overlapping pattern of gene expression. PGRP highly increased expression of genes for oxidative and disulfide stress, detoxification and efflux of Cu, As, and Zn, several transporters, repair of damaged proteins and DNA, energy generation, histidine and cysteine synthesis, envelope lysis and remodeling, and other stress responses. PGRP also caused marked decrease in the expression of genes for phosphate uptake and utilization, Fe uptake, and motility. Gene expression microarray in B. subtilis exposed to a human bactericidal innate immunity protein, PGRP, showed induction of oxidative stress response and defense genes, with different expression pattern than B. subtilis exposed to an aminoglycoside antibiotic and a membrane potential decoupler.
Project description:The bacterial cell wall has been a celebrated target for antibiotics and holds real promise as a target for the discovery of new chemical matter to surmount pervasive multi-drug resistance among pathogenic bacteria. While the walls of Gram-negative bacteria are composed primarily of peptidoglycan, those of Gram-positives are more substantial and contain, in addition, large amounts of the polymer teichoic acid, covalently attached to peptidoglycan. Wall teichoic acids are a diverse group of phosphate-rich, extracellular polysaccharides that have been largely regarded as ancillary cell surface components. Recently, wall teichoic acid was shown to be essential to the proper rod-shaped cell morphology of the prototype Gram-positive bacterium Bacillus subtilis and an important virulence factor for the human pathogen Staphylococcus aureus. Thus wall teichoic acid synthesis is an intriguing target for the development of new cell wall-active antibiotics. Nevertheless, recent studies have shown that the dispensability of genes encoding teichoic acid biosynthetic enzymes in both B. subtilis and S. aureus is paradoxical and complex. Here, we report here on the discovery of a promoter (PywaC), which is sensitive to lesions in teichoic acid synthesis. Using this promoter we developed a luminescent, cell-based, reporter system to take a chemical-genetic approach to understanding the complexity of wall teichoic acid biogenesis using a large collection of antibiotics of well characterized biological activity. Our results reveal surprising interactions among undecaprenol, peptidoglycan and teichoic acid biosynthesis that help explain the complexity of teichoic acid gene dispensability. Furthermore, the new reporter assay represents an exciting avenue for the discovery of novel antibacterial molecules that impinge broadly on Gram-positive bacterial cell wall biogenesis. Keywords: comparison between depleted and repleted tagD mutant