Summary The murein (peptidoglycan) sacculus is an essential polymer embedded in the bacterial envelope. Escherichia coli class B penicillin‐binding protein (PBP) 3 a transpeptidase and for cell division. In affinity chromatography experiment, bifunctional transglycosylase‐transpeptidase synthase PBP1B was retained by PBP3‐sepharose when membrane fraction of E. applied. direct protein–protein interaction between purified PBP3 characterized vitro surface plasmon resonance. confirmed vivo...

Bacterial cell division requires the coordinated action of proteins and murein (peptidoglycan) synthases. Interactions involving essential protein FtsN synthases were studied by affinity chromatography with membrane fraction. The PBP1A, PBP1B, PBP3 had an to immobilized FtsN. PBP3, but not showed PBP1B. direct interaction between PBP1B was confirmed pulldown experiments surface plasmon resonance. also detected bacterial two-hybrid analysis. could be cross-linked in intact cells wild type...

Cell wall thickening is a common feature among daptomycin-resistant Staphylococcus aureus strains. However, the mechanism(s) leading to this phenotype unknown. We examined number of cell synthesis pathway parameters in an isogenic strain set S. bloodstream isolates obtained from patient with recalcitrant endocarditis who failed daptomycin therapy, including initial daptomycin-susceptible parental (strain 616) and two strains (strains 701 703) isolated during therapy. Transmission electron...

Peptidoglycan (PGN) is ubiquitous in nearly all bacterial species. The PGN sacculus protects the cells against their own internal turgor making one of most important targets for antibacterial treatment. Within last sixty years composition has been intensively studied by various methods. breakthrough was application HPLC technology on analysis muropeptides. However, preparation pure relied a very time consuming method about week. We established purification protocol both Gram-positive and...

PBP1B is a major bifunctional murein (peptidoglycan) synthase catalyzing transglycosylation and transpeptidation reactions in Escherichia coli. has been shown to form dimers vivo. The K(D) value for dimerization was determined by surface plasmon resonance. effect of the on its activities studied with newly developed vitro synthesis assay radioactively labeled lipid II precursor as substrate. Under conditions at which dimerizes, enzyme synthesized long glycan strands (>25 disaccharide units)...

Multiple mechanisms have been correlated with daptomycin-resistance (DAP-R) in Staphylococcus aureus. However, one common phenotype observed many DAP-R S. Aureus strains is a thickened cell wall (CW). The first evidence for an impact of CW-linked glycopolymers on this was recently demonstrated single, well-characterized methicillin-susceptible aureus (MSSA) strain. In isolate the CW linked to increased production and D-alanylation teichoic acids (WTA). current report, we extended these...

Peptidoglycans (PGNs) are immunogenic bacterial surface patterns that trigger immune activation in metazoans and plants. It is generally unknown how complex structures such as PGNs perceived by plant pattern recognition receptors (PRRs) whether host hydrolytic activities facilitate decomposition of matrices generation soluble PRR ligands. Here we show Arabidopsis thaliana, upon infection or exposure to microbial patterns, produces a metazoan lysozyme-like hydrolase (lysozyme 1, LYS1). LYS1...

Wheat is of high importance for a healthy and sustainable diet the growing world population, partly due to its mineral content. However, several minerals are bound in phytate complex grain unavailable humans. We performed series trials compare contents phytic acid as well phytase activity varieties from alternative wheat species spelt, emmer einkorn with common wheat. Additionally, we investigated potential recent popular bread making recipes German bakeries reduce content, thus increase...

Abstract The cell wall synthesis pathway producing peptidoglycan is a highly coordinated and tightly regulated process. Although the major components of bacterial walls have been known for decades, complex regulatory network controlling many details division machinery are not well understood. eukaryotic-like serine/threonine kinase Stk cognate phosphatase Stp play an important role in biosynthesis drug resistance S. aureus . We show that stp deletion has pronounced impact on synthesis....

Staphylococcus aureus is exposed to multiple antimicrobial compounds, including oxidative burst products and antibiotics. The various mechanisms regulatory pathways governing susceptibility or resistance are complex only superficially understood. Bacillus subtilis recently has been shown control disulfide stress responses by the thioredoxin-related YjbH protein, which binds transcriptional regulator Spx controls its degradation via proteasome-like ClpXP protease. We show that S. homolog a...

Staphylococcus aureus is a facultative pathogen that can encode numerous antibiotic resistance and immune evasion genes cause severe infections. Reduced susceptibility to last resort antibiotics such as vancomycin daptomycin often associated with mutations in walRK, an essential two-component regulatory system (TCS). This study focuses on the WalK accessory membrane proteins YycH YycI their influence WalRK phosphorylation. Depletion of by antisense RNA caused impaired autolysis, indicating...

Summary I ntimin and nvasin are prototypical inverse ( T ype V e) autotransporters important virulence factors of enteropathogenic E scherichia coli Y ersinia spp . respectively. In addition to a C ‐terminal extracellular domain β‐barrel transmembrane domain, both proteins also contain short N periplasmic that, in ntimin, includes lysin motif LysM ), which is thought mediate binding peptidoglycan. We show that the does bind peptidoglycan vitro vivo , but only under acidic conditions. were...

Staphylococcus aureus is an opportunistic pathogen that causes a wide range of infections. Due to the rapid evolution antibiotic resistance leads treatment failure, it important understand underlying mechanisms. Here, cell wall structures several laboratory vancomycin-intermediate S. (VISA) strains were analyzed. Among VISA VC40, which accumulated 79 mutations, including most importantly 2 exchanges in histidine-kinase VraS, and developed full against vancomycin (MIC, 64 μg/ml); revertant...

Abstract As a lipopeptide (LP), surfactin exhibits properties, such as emulsifying and dispersing ability, which are useful in food industry. Discovery of new LP-producing strains from sources is an important step towards possible application foods. A total 211 spore-forming, Gram-positive, catalase-positive bacterial were isolated fermented African locust beans (iru) palm oil mill effluents screening process examined for their ability to produce surfactin. This was achieved by combination...

Introduction:B. velezensis strains are of interest in agricultural applications due to their beneficial interactions with plants, notable through antimicrobial activity. The biocontrol ability two new lipopeptides-producing B. ES1-02 and EFSO2-04, against fungal phytopathogens Diaporthe spp., was evaluated compared reference QST713 FZB42. All were found be effective the plant pathogens, showing comparable antifungal activity slightly lower than Methods: Lipopeptides isoforms identified by...

The Gram-positive bacterium Staphylococcus carnosus (S. carnosus) TM300 is an apathogenic staphylococcal species commonly used in meat starter cultures. As with all bacteria, its cytoplasmic membrane surrounded by a thick peptidoglycan (PGN) or murein sacculus consisting of several layers glycan strands cross-linked peptides. In contrast to pathogenic staphylococci, mainly aureus aureus), the chemical composition S. PGN not well studied so far. UPLC/MS analysis enzymatically digested...

Abstract Aspergillus fumigatus is a saprophytic fungus dwelling in soil and on decaying plant material, but also an opportunistic pathogen immunocompromised patients. In its environmental niche, A. faces competition from other microorganisms including bacteria. Here, we describe the discovery of first secreted antibacterial protein . We identified fungal endopeptidase, designated CwhA, that cleaves peptidoglycan Gram-positive bacteria at specific residues within stem peptide. Cleavage leads...