| Title | Trichoderma koningii에서 분리한 β-1,4-D-glucan glucanohydrolase의 특성 Characterization of β-1,4-D-glucan glucanohydrolase purified from trichoderma koningii | ||
| Author | 임대식 · 정춘수 · 강사욱 · 하영칠 | ||
| Address | 서울대학교 자연과학대학 미생물학과 | ||
| Bibliography | Korean Journal of Microbiology, 29(2),85-91, 1991 | ||
| DOI | |||
| Key Words | β-1,4-D-Glucan Clucanohydrolase, PNP derivatives(PNP, PNPG_1, PNPG_2, PNPG_3) | ||
| Abstract | β-1,4-D-Glucan glucanohydrolase(EC 3.2.1.4;F-II-IV) purified from Trichoderma koningii was identified as a glycoprotein containing 9% carbohydrate. Isoelectric point of the enzyme was estimated to be 4.9 and molecular weight was determined to be approximately 58,000. The porducts of p-nitrophenyl-cellobioside (PNPG_2) catalyzed by the enzyme were p-nitrophenol(PNP) and p-nitrophenyl-glucoside(PNPG_1). The Km value for PNPG_2 was estimated to be 0.97 mM in case of the holoside lindage and 10.4 mM in case of the aglycon linkage and their kcat values were 1.8×10^5 min^-1 and 7.5×10^5 min^-1, respectively. The product of p-nitrophenyl cellotriose(PNPG/_3) was only PNPG_1. The Km value for PNPG_3 was 69.5 uM and kcat was 1×10^8 min^-1, which implicates that the enzyme have higher affinity and higher hydrolysis rate toward PNPG_3 than toward PNPG_2. The enzyme showed its optimal activity at pH 4.0-4.5 and at 60℃. The effect of gluconolactone on the activity toward PNPG_2 showed competitive inhibition pattern but glucose and cellobiose did not. The enzyme contained a high content of acidic and hydroxylated amino acids in contrast to basic amino acids. | ||
| Download PDF | Kor_290203_85-91p.pdf | ||