BIOSYNTHESIS OF GRAMICIDIN AND TYROCIDINE IN THE DUBOS STRAIN OF BACILLUS BREVIS I

Abstract

Biosynthesis of gramicidin and tyrocidine in the Dubos strain of Bacillus brevis. I. Experiments with growing cultures. J. Bacteriol. 85:329-338. 1963.-A simple chromatographic method was developed for the isolation of gramicidin and tyrocidine from tyrothricin of Bacillus brevis. A Tryptone-yeast extract-glucose medium containing mineral salts gave the best yields of peptides in a stationary culture of the organism. The incorporation of suitable C'4-labeled amino acids into gramicidin and tyrocidine was studied Several analogues of tyrocidine amino acids (,B-hydroxyglutamic acid, pipecolic acid, ,B-2thienylalanine, p-fluorophenylalanine, and phenyl glycine) selectively reduced tyrocidine synthesis, when added to the nutrient medium. At the same time, the production of gramicidin was augmented. Growth and protein synthesis were not affected. Two analogues in isotopic form, ,B-2thienylalanine and isoleucine, were shown to give rise to high degrees of labeling in tyrocidine. Radioactive amino acids. DL-Pipecohic acid-H3 was a previously described preparation (Winnick and Winnick, 1961); DL-f3 (2-thienyl) alanine-3-C'4 and glycine-1-C14 were obtained from the Commissariat A l'Energie Atomique, France. DL-Proline-l-C'4, DL-ornithine-2-C'4, DL-valine-1-C14, and ethanolamine-1,2-Cl4 were from the California Corporation for Biochemical Research. L-Isoleucine-U-Cl4 was purchased from the Radiochemical Centre, England. Amino acid analogues. DL-p-Fluorophenylalanine, phenylglycine, DL-pipecolic acid, and DL-f-2-thienylalanine were purchased from the California Corporation for Biochemical Research.

The peptide antibiotics of Bacillus: chemistry, biogenesis, and possible functions.

“…In vivo (102,112,130,168) as well as in vitro (30,33,34,37,58,63,93,97,120,128,153) experiments have revealed that structurally similar amino acids and amino acid analogues can replace certain of the amino acid residues of the peptide chain during antibiotic synthesis. These studies have demonstrated that antibiotic formation is catalyzed by enzymes with rather broad specificities.…”

Modelling the variable incorporation of aromatic amino acids in the tyrocidines and analogous cyclodecapeptides

“…The tyrothricin producer bacterial strain was initially referred to as the Dubos strain of Bacillus brevis (Okuda et al ), and renamed to Bacillus aneurinolyticus (Shida et al ). These authors subsequently suggested further reclassification of the strain to Br.…”

The use of acid alumina and Sephadex LH-20 for the separation and characterization of ethanol-soluble peptides produced by Bacillus brevis

“…(Uemura et al, 1963) or butan-l-ol-acetic acid-water (12:3:5, by vol.). Papers were air-dried, and gramicidin and tyrocidine were detected either by dipping the paper in 7M-HN03 (Okuda et al, 1963), when yellow spots appeared on a white background (detection limits 5S,g of tyrocidine and 3,ug of gramicidin), or by dipping the paper in or spraying it with 0.2 % (w/v) ninhydrin in dry acetone and heating it at 60°C for 30min; tyrocidine gave a blue-grey spot and gramicidin a grey spot (detection limit about 100,ug in each case).…”