Role of aliphatic acids in the biosynthesis of vermiculin in penicillium vermiculatum.

The diolode macrolide vermiculin (1) together with the three unsaturated aliphatic ketoacids vermiculinic (2), vermiculic (3) and 4-deoxovermiculic acid (4) were isolated from the cultivation broth of Penicillium vermiculatum. Biotransformation of 2 and 3 with growing and resting cells of P. vermiculatum was studied. We suppose, that 2 which is formed from 3, is the ultimate progenitor of 1.