Analysis of a gene cluster from S. longisporoflavus potentially involved in tetronasin biosynthesis.

Tetronasin (formerly ICI139603) [l] is a polyether polyketide antibiotic produced during the aerobic growth of the Gram-positive soil organism Streptomyces longisporofluvus. It has been used c o m i a l l y as a cattle food additive where it has been found to improve food utilisation [2] and to combat the onset of acid lactosis [3]. It may well also prove to be commercially viable as an anticwidant for use in the poultry industry.