Bacteriocins represent a large family of ribosomally produced peptide antibiotics. Here we describe the discovery of a widely conserved biosynthetic gene cluster for the synthesis of thiazole and oxazole heterocycles on ribosomally produced peptides. These clusters encode a toxin precursor and all necessary proteins for toxin maturation and export. Using the toxin precursor peptide and heterocy...

The biochemical characteristics of specific receptor molecules for diphtheria toxin on the surface of two toxin-sensitive cell lines (Vero and BS-C-1) were examined. Diphtheria toxin was found to bind to a number of different proteins in Nonidet P-40 solubilized extracts of 125I-labeled cells. In contrast, permitting diphtheria toxin to bind first to labeled intact cells, which were subsequentl...

A simple purification scheme for shigella cytotoxin was devised, resulting in high yields (approximately 50%) and a 1,300-fold increase in specific activity compared with the initial crude bacterial cell lysate. The purified toxin was enterotoxic in ligated rabbit ileal loops and neurotoxic when injected into the peritoneal cavity of mice. Measurement of specific activity of cytotoxin and enter...

The killer toxin from Pichia membranifaciens CYC 1106, a yeast isolated from fermenting olive brines, binds primarily to the (1-->6)-beta-D-glucan of the cell wall of a sensitive yeast (Candida boidinii IGC 3430). The (1-->6)-beta-D-glucan was purified from cell walls of C. boidinii by alkali and hot-acetic acid extraction, a procedure which solubilizes glucans. The major fraction of receptor a...

Vascular dysfunction has been reported in human cases of anthrax, in mammalian models of Bacillus anthracis, and in animals injected with anthrax toxin proteins. To examine anthrax lethal toxin effects on intact blood vessels, we developed a zebrafish model that permits in vivo imaging and evaluation of vasculature and cardiovascular function. Vascular defects monitored in hundreds of embryos e...

The isolation of Clostridium botulinurn type A toxin in crystalline form (1, 2) has led to an interest in its chemical composition. An apparently complete analysis of the pure crystalline toxin is presented in this paper. Preliminary studies have indicated that the toxin is a protein with an isoelectric point of pH 5.6, possessing the properties of a globulin (l-3). It is free from carbohydrate...

The killer toxin from Pichia membranifaciens CYC 1106, a yeast isolated from fermenting olive brines, binds primarily to the (136)-b-D-glucan of the cell wall of a sensitive yeast (Candida boidinii IGC 3430). The (136)-b-D-glucan was purified from cell walls of C. boidinii by alkali and hot-acetic acid extraction, a procedure which solubilizes glucans. The major fraction of receptor activity re...