논문 상세보기
pp.43-49
최소 배지에 여러 퓨린 분해 대사 산물을 첨가하여 배양시킨 Serratia marcescens ATTC 25419 세포 추출물에서 purine nucleoside phosphorylase(PNP)의 활성을 조사한 결과, 구아노신은 대조군에 비해 효소의 활성을 5∼15mM에서 60% 이상 감소시켰고, 이노신은 7∼15mM에서 30% 정도 감소시켰으나 0.1∼1mM에서 효소의 활성을 원래대로 회복시켰다. 아데노신, 히포크산틴 및 크산틴도 5∼15mM에서 효소의 활성을 40∼50%정도 감소시켰으나 0.1∼0.5mM에서는 원래대로 회복시켰다. 한편, 요산은 효소의 활성을 0.5mM에서 20% 증가시킨 반면 15mM에서 80% 감소시켰다. 요산의 최종 분해 산물인 글리옥실산도 효소의 활성을 0.5mM에서 20% 증가시킨 반면 3∼15mM에서 30∼50% 정도 감소시켰다. 5mM 농도의 이노신, 히포크산틴 및 요산을 동시에 첨가했을 경우 효소의 활성을 20% 정도 감소된 반면, 이노신과 요산, 세 퓨린 분해 대사 산물은 각각 0.5mM씩 동시 첨가했을 경우는 각각 22, 33%씩 증가시켰다. 이 결과는 낮은 농도 (0.5mM)의 글리옥실산이 S. marcescens purine nucleoside phosphorylase (PNP)의 활성을 증가시키고 고 농도의 글리옥실산은 감소시키는 것을 나타내기 때문에 퓨린 분해 대사 과정에서 글리옥실산이 PNP 생합성의 조절 역할을 하는 것으로 분석된다.
The effects of purine catabolites in growth media on the Serratia marcescens purine nucleoside phosphorylase activity were examined. The enzyme activity was decreased above 60% by guanosine (5 to 15mM). The enzyme activity was decreased approximately by 30% in the presence of high concentrations of inosine (7∼15mM), but was not affected at low concentration of inosine (0.1∼1mM). The enzyme activity was decreased approximately by 40∼50% in the presence of high concentrations of adenosine, hypoxanthine, and xanthine (5∼15mM), but was not affected at low concentration of adenosine, hypoxanthine, and xanthine (0.1∼0.5mM). However, the enzyme activity was increased by 20% with low concentrations of uric acid (0.5mM), but was decreased by 80% with high concentrations of same purine catabolite (15mM). Also, the enzyme activity was increased by 20% with low concentration of glyoxylate (0.5mM), final degradative product of uric acid , but was decreased by 30∼50% with high concentrations of glyoxylate (3∼15mM). The enzyme activity was decreased approximately by 20% by the simultaneous addition of inosine, hypoxanthine and uric acid at 5mM each, whereas it was increased by 22 and 33% by the combination of inosine and uric acid, three purine catabolites at 0.5 mM, respectively. These data suggest that S. marcescens purine nucleoside phosphorylase is positively regulated by a glyoxylate concentration, and then may play a regulatory role in a purine catabolism.
