Cellulomonas sp. YE-5가 생산하는 Cellulase의 정제

Purification of Cellulase Produced from Cellulomonas sp. YE-5

토양과 퇴비 등에서 섬유소 자화력이 있는 세균을 분리하고 이 균주들 중 cellulase 생산능이 가장 우수한 균주를 선별하여 Cellulomonas sp.로 동정하였다. Cellulomonas sp. YE-5의 최적 배양조건은 pH6.5 Solka floc 0.8(w/v), urea 0.06(w/v), K2HPO4 0.1(w/v), bacto peptone 0.2(w/v), yeast extract 0.2(w/v) 그리고 MgSO4.7H2O 0.0(w/v) 이었으며, 이러한 배지를 사용하여 $30^{\circ}C$ 에서 48시간 배양하였을 때 avicelase, CMCase 그리고 Beta-glucosidase는 각각 0.350, 3.180, 0.882units/ml의 활성을 나타내었다.

An extracellular cellulase producing bacterium YE-5 was isolated from soil, and identified as a Cellulomonas sp. by its taxonomical characteristics. The maximal activities of avicelase (0.35 units/ml), CMCase (3.18 units/ml), FPase (0.315 units/ml) and $\beta$-glucosidase (0.882 units/ml) were obtained when this strain was cultured for 48 hrs at $30^{\circ}C$ in a medium containing 0.8% (w/v) Solka floc, 0.06010 (wlv) urea, 0.1% (w/v) $K_2HP0_4$, 0.1% (w/v) $MgS0_4.7H2_0$, 0.2% (w/v) bacto peptone, 0.2% (w/v) yeast extract and pH 6.5. The cellulase was purified by ammonium sulfate fractionation, DEAE-Sepharose column chromatography and Sephadex 6-100 column chromatography from culture filtrate of Cellulomonus sp. YE-5. The molecular weights of purified avieelase, CMCase I, and CMCase II were estimated to be about 95,000 ~ 105,000, 46,000 ~ 47,000 and 120,000 ~ 125,000, respectively.