IMPROVEMENT OF CEPHAMYCIN-C PRODUCTION BY A MUTANT RESISTANT TO LINOLEIC-ACID

Streptomyces sp. P6621 was very sensitive to linoleic acid when soybea n oil was used as the sole carbon source for the production of cephamy cin C. Cell growth was strictly restrained by adding 0.25 g/l of linol eic acid to the culture. An ultraviolet-induced mutation was performed based on the hypothesis that a mutant resistant to linoleic acid coul d produce antibiotics more efficiently. Mutant strain U-12-2 resistant to 0.4 g/l of linoleic acid was obtained by screening in solid and li quid media containing linoleic acid. The uptake rate of linoleic acid by U-12-2 was three times higher than that by the parental strain. Cep hamycin C production from 30 and 60 g/l of soybean oil as the sole car bon source was 1.6 fold higher with the mutant strain compared to the parental strain. It is concluded that this mutant which is resistant t o linoleic acid has improved cephamycin C production.