Microbial Transformations Of Antibiotics

Abstract

In spite of their unusual molecular structures and seemingly high degree of biological recalcitrance, many antibiotics have been shown to be susceptible to microbial attack. Among the types of changes brought about by microbial systems are: (i) acylation; (ii) phosphorylation; (iii) adenylylation and ribonucleotide formation: (iv) hydrolysis; (v) oxidation; (vi) sulphoxidation; (vii) reduction; (viii) demethylation; and (ix) deamination. The choice of organisms to carry out specific types of transformations of an antibiotic has rarely been done on a logical basis. Random screening of cultures known to transform steroids, of cultures which are known to be resistant to the antibiotic under study, of the antibiotic-producing organism, and of organisms selected from soil (or other sources) by enrichment techniques, have all been successfully used. With a few exceptions the transformations so far reported have resulted in biological inactivation of the antibiotic. However, some of the products of the transformation are useful as intermediates in chemical synthesis of new antibiotics, e.g. 6-aminopenicillanic acid for the preparation of new penicillins. Others including streptomycin (formed from mannosidostrepto-mycin) are more active than the starting material. © 1971, Walter de Gruyter. All rights reserved.