SYNTHESIS OF BEAUVERICIN BY A MULTIFUNCTIONAL ENZYME

• Published in: Journal of antibiotics Vol. 41; no. 3; pp. 352 - 359
• Main Authors: PEETERS, HUGO, ZOCHER, RAINER, KLEINKAUF, HORST
• Format: Journal Article
• Language: English
• Published: Tokyo JAPAN ANTIBIOTICS RESEARCH ASSOCIATION 1988; Japan Antibiotics Research Association
• Subjects: Anti-Bacterial Agents - biosynthesis; Beauveria bassiana; beauvericin; beauvericin synthase; Biological and medical sciences; Biology of microorganisms of confirmed or potential industrial interest; Biotechnology; Depsipeptides; Fundamental and applied biological sciences. Psychology; Growth, nutrition, metabolism, transports, enzymes. Molecular biology; Hydrogen-Ion Concentration; Kinetics; Methylation; Microbiology; Mission oriented research; Mitosporic Fungi - enzymology; Molecular Weight; Mycology; Peptide Synthases - analysis; Peptides; Peptides, Cyclic - biosynthesis; Physiology and metabolism; Substrate Specificity; Temperature; Purification; Cyclic peptides; Biosynthesis; Fungi; Characterization; Beauveria bassiana; Antibiotic; Depsipeptide; Substrate specificity; Reaction mechanism; Mixed-function enzyme; Fungi Imperfecti; Ionophore; Catalyst activity; Microbial insecticide; Physicochemical properties; Thallophyta
• ISSN: 0021-8820; 1881-1469
• DOI: 10.7164/antibiotics.41.352

Beauvericin synthetase, a multifunctional enzyme catalyzing depsipeptide formation in Beauveria bassiana was purified to near homogeneity. The enzyme consists of a single polypeptide chain with a molecular mass of about 250 kdaltons. The mechanism of beauvericin formation is very similar to that of the cyclohexadepsipeptide enniatin. The constituents of the beauvericin molecule, L-phenylalanine and D-α-hydroxyisovaleric acid are activated as thioesters via the corresponding adenylates. N-Methylation takes place at the thioester bound stage of the phenylalanine residues. Omission of the methyl donor S-adenosyl-L-methionine results in the formation of demethylbeauvericin. Studies on substrate specificity revealed that phenylalanine could be replaced by a number of other aromatic or aliphatic amino acids like β-phenylserine, ortho-, meta-, pam-ftuorophenylalanine, isoleucine, norleucine and leucine. Valine, the constituent amino acid of enniatin B was not accepted by the enzyme.