Biosynthesis of Depsipeptide Mycotoxins in Fusarium |
| |
| Authors: | Till Hornbogen Mirko Glinski Rainer Zocher |
| |
| Institution: | (1) Fakultät II, Institut für Chemie, Arbeitsgruppe Biochemie und Molekulare Biologie, Technische Universtät Berlin, Franklinstrasse 29, D-10587 Berlin, Germany |
| |
| Abstract: | The cyclic hexadepsipeptide enniatin is known as a phytopathogenic compound from Fusaria causing necrosis and wilt. The molecule consists of three alternating residues each of a branched chain amino acid and D-hydroxyisovaleric acid (D-Hiv). Enniatins are synthesized by a 347kDa multienzyme (enniatin synthetase) via a thiol template mechanism. The corresponding gene esyn1 has an open reading frame of 9393 nucleotides and harbours two modules, one responsible for D-hydroxy acid activation and one for L-amino acid activation with an integrated N-methyltransferase domain. Such methyltransferases build an homologous group among N-methyl peptide synthetases. Enniatins are synthesized by step-wise condensation of dipeptidol building blocks in an iterative manner resembling fatty acid synthesis. A key enzyme in enniatin biosynthesis is the NADPH-dependent D-2-hydroxyisovalerate dehydrogenase, that supplies enniatin synthetase with D-Hiv. Enniatins contribute to the wilt toxic character of Fusaria. Virulence was significantly reduced in F. avenaceum after disruption of the esyn1 gene. |
| |
| Keywords: | enniatin synthetase Fusarium N-methylated cyclodepsipeptides nonribosomal peptide synthesis phytopathogenic |
| 本文献已被 SpringerLink 等数据库收录！ |
