Iturin AL - A new long chain iturin a possessing an unusual high content of C16-.BETA.-amino acids.

Abstract

From a strain of Bacillus subtilis a new antifungal peptidolipid complex of the iturin group was isolated. This antibiotic complex contained six lipophilic j3-amino acids with 3-amino-14-methylpentanoic acid as the predominant component.L-Ser, 1 D-Tyr and a mixture of 2.9 % iso-C, -~-amino acid, 30.7 % n-C14-(3-amino acid, 15% iso-C1,-(3-amino acid, 9 % anteiso-C,,-(3-amino acid, 35.3% iso-C16-/3-amino acid and 4.5 % n-C16-(3-amino acid. The structures of the p-amino acids were determined by combined GLC/MS. FAB mass spectroscopy revealed three M+H+ peaks (1,043, 1,057, 1,071). Iturin AL could be resolved into six components by HPLC whose structures confirm the high amount of long chain (3-amino acids.Cyclic peptidolipidic antibiotics of the iturin group, such as iturin A and iturin C, have been isolated and described by PEYPOUX, DELCAMBE and co-workers1.1,1). Recently the structures of the R-amino acids of iturin A isolated from two different Bacillus subtilis strains were compared by mass spectroscopy and 13C NMR4). These data revealed that iturin A is composed of a constant set of a-amino acids and a collection of 3-amino acids in which the C14 Q-amino acids and C15-p-amino acids predominate. The present investigation, however, shows that there exist B. subtilis strains, which, under identical media and growth conditions, biosynthesize a mixture of homologous peptides in which the C16-ji-amino acids prevail.Fermentation

Genomic variability in Vitis vinifera L. Sangiovese assessed by microsatellite and non-radioactive AFLP test

“…On the other hand, bacillomycin D is insoluble in water and in most organic solvents (Peypoux et al 1980). A new antifungal peptidolipid antibiotic, iturin A L , isolated from a strain of B. subtilis, was soluble in methanol and ethanol and barely soluble in water, enough though to allow its detection by diffusion in agar (Winkelmann et al 1983). Later, Schreiber et al (1988) isolated from Ulmus americana a metabolite of 500 D, soluble in water, methanol, ethanol and chloroform, quite similar to the antifungal metabolites described by McKeen et al (1986).…”

Surfactin and Other Lipopeptides from Bacillus spp.

“…Iturin A and C and bacillomycin D, L, each display a fatty acyl chain with a length of 14 and 15 C, while the C16 and C17 forms are the main representative fatty acid of the bacillomycin F and the mycosubtilin. A form of Iturin A with long fatty acyl chain (C16) was identified by Winkelmann et al (1983) and called Iturin A L .…”

A note on the antibiotic properties of Bacillus subtilis against Colletotrichum trifolii

“…Compounds were detected using an UV lamp at 254 nm, and by application of a solution of ninhydrin that was then developed at 110°C for 10 min to detect free amino groups (Winkelmann et al 1983). Compounds which are insoluble in water, such as lipids, were detected by spraying the plates with water (Bobitt 1963 Numbers are the means of observations from two répétitions of the experiment.…”