FACTORS AFFECTING THE NORMAL AND BRANCHED-CHAIN ACYL MOIETIES OF TEICOPLANIN COMPONENTS PRODUCED BY ACTINOPLANES-TEICHOMYCETICUS

Teicoplanin, a glycopeptide antibiotic produced by Actinoplanes teichomyceticus, comprises five main components, denoted T-A2-1 to T-A2-5, differing in the structure of their acyl side chain, which is linear in T-A2-1 and T-A2-3 and branched in the other components. Production of T-A2-1, characterized by a linear C10:1 acyl moiety, is entirely dependent on the presence of linoleate in the fermentation medium. Addition to the medium of oleic acid esters at 2 g I-1 increases the yields of T-A2-3, characterized by a linear C10:0 acyl chain, about threefold. The antibiotic linear side chains thus appear to originate from C18 unsaturated acid by beta-oxidation degradation. The percentage of T-A2-2, T-A2-4 and T-A2-5, bearing the iso-C10:0, anteiso-C11:0 and iso-C11:0 acyl moieties, respectively, is strongly influenced by the presence in the medium of the amino acids known to be precursors of branched-chain fatty acids. Thus, valine increases the production of T-A2-2 whereas isoleucine or leucine increase the relative yields of T-A2-4 or T-A2-5, respectively. Analysis of the total cell lipids upon addition of the same amino acid shows corresponding increases in the proportion of the iso-C16:0, iso-C15:0 or anteiso-C17:0. A mutant A. teichomyceticus strain, which produces a novel teicoplanin with a linear C9:0 chain, differs from the wild strain in the presence of the linear C17:1 acid in its lipids. The relative incorporation of [C-14]acetate into teicoplanin acyl moieties is substantially lower when this precursor is added to grown A. teichomyceticus mycelium rather than at the time of inoculation. The results suggest that teicoplanin branched acyl moieties also originate from beta-oxidation degradation of cellular long-chain fatty acids.