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Teicoplanin, a glycopeptide antibiotic produced by Actinopfanes teichornyceticus, 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 C1O:l 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 1-l increases the yields of T-A2-3, characterized by a linear C1O:O acyl chain, about threefold. The antibiotic linear side chains thus appear to originate from C18 unsaturated acid by P-oxidation degradation. The percentage of T-A2-2, T-A2-4 and T-A2-5, bearing the iso-ClO:O, anteiso-Cll :O and iso-Cl1 :O 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-Cl6 : 0, iso-Cl5 : 0 or anteiso-C17 : 0. A mutant A. teichornyceticus strain, which produces a novel teicoplanin with a linear 0 : 0 chain, differs from the wild strain in the presence of the linear C17: 1 acid in its lipids. The relative incorporation of [14C]acetate into teicoplanin acyl moieties is substantially lower when this precursor is added to grown A. teichornyceticus mycelium rather than at the time of inoculation. The results suggest that teicoplanin branched acyl moieties also originate from P-oxidation degradation of cellular long-chain fatty acids.

Structures of the fatty acid residues characterizing the various components of A40926 were determined by gas chromatography/mass spectrometry on the methyl esters obtained by methanolysis of the complex. The results confirm the residues previously assigned to Factor A (n-undecanoic acid) and B (10-methyl-undecanoic acid) and establish the residues of Factor A1 (9-methyl-decanoic acid), B1 (n-dodecanoic acid), RS1 (8-methyl-nonanoic acid), RS2 (n-decanoic acid), and RS3 (n-tridecanoic acid). As the Actinomadura species contain in their mycelia large quantities of C15-C17 fatty acid residues as membrane phospholipids, these mycelia were saponified and the fatty acids obtained were analyzed as above. There is a close correlation between the fatty acid content of A40926 complex and that of the longer homologues in the producer mycelia.

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