Ramoplanin, a new lipoglycopeptide antibiotic, inhibits cell wall peptidoglycan biosynthesis in gram-positive bacteria. In both Staphylococcus aureus and Bacillus megaterium, UDP-N-acetylmuramyl-pentapeptides (UDP-MurNAc-pentapeptides) accumulated at concentrations of ramoplanin close to the MIC, indicating that inhibition of peptidoglycan biosynthesis occurred after formation of cytoplasmic pr...

Our previous studies have shown that lactic acid bacteria (LABs) can bind and remove di-n-butyl phthalate (DBP), diethyl phthalate, dioctyl phthalate; three ubiquitous environmental contaminants. In this study, Lactobacillus acidophilus NCFM was chosen to study the DBP binding mechanism. We found three-dimensional structure of bacterial cell wall, including carbohydrates proteins, essential for...

Peptidoglycan performs the essential role of resisting turgor in the cell walls of most bacteria. It determines cell shape, and its biosynthesis is the target for many important antibiotics. The fundamental chemical building blocks of peptidoglycan are conserved: repeating disaccharides cross-linked by peptides. However, these blocks come in many varieties and can be assembled in different ways...

Several species of Gram-positive bacteria have cell wall peptidoglycan (syn. murein) in which not all of the sugar moieties are N-acetylated. This has recently been shown to be a secondary effect, caused by the action of a peptidoglycan N-acetylglucosamine deacetylase. We have found that the opportunistic pathogen Listeria monocytogenes is unusual in having three enzymes with such activity, two...

The O acetylation of peptidoglycan occurs specifically at the C-6 hydroxyl group of muramoyl residues. Using a combination of high-performance liquid chromatography-based organic acid analysis and carbohydrate analysis by high-pH anion-exchange chromatography, we determined that strains of Entercoccus durans, E. faecalis, E. faecium, and E. hirae produce O-acetylated peptidoglycan. The levels o...

Neisseria gonorrhoeae gonococcus (GC) is a Gram-negative betaproteobacterium and causative agent of the sexually transmitted infection gonorrhea. During growth, GC releases lipooligosaccharide (LOS) and peptidoglycan (PG) fragments, which contribute significantly to the inflammatory damage observed during human infection. In ascending infection of human Fallopian tubes, inflammation leads to in...

Whole cells and peptidoglycan isolated from cell walls of the cyanobacterium Anabaena flos-aquae were lyophilized and used at pH 2 and pH 5 in Cu(II) binding studies. X-ray absorption spectra measured at the Cu K-edge were used to determine the oxidation states and chemical environments of Cu species in the whole-cell and peptidoglycan samples. In the whole-cell samples, most of the Cu retained...

In the present studies we compared the ability of two commonly used assays, solid-phase radioimmunoassay and enzyme-linked immunosorbent assay (ELISA), to detect human antibodies to Staphylococcus aureus peptidoglycan. ELISA was superior, with a reproducibility of 12.0%, as compared with 18.1% in solid-phase radioimmunoassay. Much lower serum dilutions could be used in ELISA. We also studied th...

Type IV secretion systems require peptidoglycan lytic transglycosylases for efficient secretion, but the function of these enzymes is not clear. The type IV secretion system gene cluster of Neisseria gonorrhoeae encodes two peptidoglycan transglycosylase homologues. One, LtgX, is similar to peptidoglycan transglycosylases from other type IV secretion systems. The other, AtlA, is similar to endo...