섬유소 분해효소 생성균주인 Trichoderma viride QM9414를 CMC에서 배양시 생성된 섬유소 분해효소들의 성질과 cotton, carboxymethylcellulose(CMC) 그리고 cellobiose 분해 기작을 조사하였으며, culture filtrate를 $(NH_4)_2SO_4$ fractionation, gel filtration과 DEAE-Sephadex column chromatography를 통해 cotton 분해력, CMC 분해력 그리고 cellobiose 분해력의 분리를 시도하였다. 얻어진 결과는 다음과 같았다. 1. Cotton activity, CMC activity, 그리고 ${eta}$-glucosidase의 최적 활성 pH는 4.8-5.2로 나타났다. 2. Cotton activity의 최적활성온도는$50^{circ}C$이며 CMC activity는 $55^{circ}C$로 나타났고 ${eta}$-glucosidase는 $40^{circ}C$ 최적활성 온도로 나타났다. 3. CMC에 의해서 유도된 섬유소 분해효소는 결정형 섬유소나 cellobiose에 의해서 유도된 섬유소 분해효소와는 달리 높은 ${eta}$-glucosidase를 보였다. 4. CMC에 의해서 유도된 섬유소 분해 효소 농축액을 Sephadex G-75 gel에 통과시켰을 때 고분자 섬유소 분해효소와 CMC에 대해서만 낮은 역가를 보여주는 저분자 CMCase가 분리되었으며 이 고분자 섬유소 분해 효소 분획을 다시 Bio Gel P-150에 통과시킨 결과 대부분의 ${eta}$-glucosidase와 cotton 분해 효소가 CMC 분해 효소로 부터 분리되었다. CMC 분해 효소 분획은 DEAE Sephadex A-50 이온교환수지에 재통과시켜 잔여 ${eta}$-glucosidase를 제거하고 CMC 분해효소만 단리하였다. 5. T. viride QM9414로부터 CMC에 의해서 유도된 섬유소 분해효소 분획들은 모두 cotton과 CMC를 분해하여 glucose와 cellobiose를 생성하였는데 최종 산물은 주로 glucose 였다. 6. CMCase는 endoglucanase와 exoglucanase 활성을 둘다 갖고 있는 것처럼 보였고 CMC와 cellobiose로부터 ${eta}$-glucosidase 존재 여부와 관계없이 glucose를 생성하였다. 7. 이 연구의 결과를 종합하여 Trichoderma viride cellulase의 cellulose 분해 작용 기작을 제안하였다.
In order to investigate the characteristics of cellulases induced by carboxymethylcellulose, Trichoderma viride QM 9414 was cultured on CMC. The culture filtrates were concentrated by $(NH_4)_2SO_4$ fractionation and used as enzyme sources. The enzyme preparations were further purified by gel filteration and DEAF-Sephadex chromatography and assayed for cotton activity, CMC activity and ${eta}$-glucosidase activity. The following results were obtained: 1. The optimum pH of the cotton activity, CMC activity and ${eta}$-glucosidase activity were between pH 4.8-5.2. 2. The optimum temperature of the cotton activity was $50^{circ}C$ and of CMC activity $55^{circ}C$, but the optimum temperature of the ${eta}$-glucosidase activity was $40^{circ}C$. 3. Cellulose induced by CMC contained high ${eta}$-glucosidase activity compared with cellulase induced by Avicel and cellobiose. 4. A low-molecular weight CMCase activity was separated from the rest by Sephadex G-75 gel and most of ${ata}$-glucosidase activity was spearated by Bio P-150 column chromatography. The remaining ${eta}$-glucosidase was separated from CMC ase by DEAE-Sephadex chromatography. From these, a cellulase that could only degrade CMC and cellobiose but not crystalline cellulase were obtained. 5. Trichoderma cellulases induced by CMC could hydrolyze cotton, CMC, and cellobiose into glucose. 6. CMCase has both endoglucanase and exoglucanase activity which degrade cellooligesaccharides and cellobiose readily into glucose in the absence of ${eta}$-glucosidase. 7. On the basises of results obtained from this study a mechanism of Trichoderma viride cellulases is proposed.
