Distribution and Substrate Specificity of 5-fluorocytosine Deamiase in Bacteria

세균의 5-Fluorocytosine Deaminase의 분포와 기질 특이성

Distribution and substrate specificity of 5-fluorocytosine deaminase were studied in various genera of bacteria. 5-Fluorocytosine deaminase was produced by various bacteria independent of genus and species and it catalyzed the deamination of cytosine, 5-fluorocytosine and 5-methylcytosine. Xanthomonas campestris IAM 1671 produced relatively large amount of 5-fluorocytosine deaminase. The composition of optimum culture medium for enzyme production wat glycerine 0.5％, peptone 1％, yeast extract 0.5％, NaCl 0.5％ and the initial pH of the medium was 7.5. The highest enzyme formation was observed after 24 hours of cultivation In 500$m\ell$ shaking flask containing 90$m\ell$ of medium at 3$0^{\circ}C$ on a reciprocal shaker.

여러 가지 속의 세균을 대상으로 5-fluorocytosine deaminase의 생산균과 기질 특이성을 검토한 결과, 5-fluorocytosine deaminase의 생산성은 종, 속에 관계없이 다양하게 나타났으며 기질로서는 cytosine, 5-fluorocytosine, 5-methylcytosine이 모두 이용될 수 있는 것으로 나타났다. 효소 생산균 중에서 비교적 활성이 높다고 인정되는 Xanthomonas campestris IAM 1671의 효소 생산을 위한 배지의 조성은 glycerin 0.5%, peptone 1%, yeast extract 0.5%. NaCl 0.5% (pH 7.0)로 설정하였다. 본 균의 효소 생산은 500$m\ell$용 진탕 flask에 효소생성 최적배지 90$m\ell$를 넣어 3$0^{\circ}C$에서 24시간 배양했을 때 최대로 나타났다.