Isolation of Genes Containing Adenylate-Forming Catalytic Domains in Syringomycin Biosynthesis by Pseudomonas Syringae PV. Syringae

Abstract

The economically important plant pathogen Pseudomonas syringae pv. syringae produces the potent phytotoxin, syringomycin, which contributes to virulence in a wide range of crops [1,2]. The primary structure of syringomycin has been determined (Fig. 1, [3,4]) and, characteristically, it was shown that the toxin is not a single molecule but a mixture of closely related lipodepsinonapeptides. The cyclic peptide portion that constitutes the polar head of the toxins are identical in all of the molecules whose structure has been determined to date; the hydroxylated fatty acid tail is, however, variable in length. The peptide portion of the molecule is novel in that it contains amino acids in both the D- and the L- isomeric forms and because some of the amino acids are derivatised by chlorination and hydroxylation [3,4].