Biosynthesis of valanimycin.

In the biosynthesis of valanimycin, valine is mostly incorporated into the isobutyl moiety of the antibiotic. The alpha-substituted acrylic moiety of valanimycin is derived from alanine. However, a part of alanine is metabolized into valine, thus incorporated also into the isobutyl moiety. Anaerobic conditions and some reducing agents strongly inhibit the biosynthesis.