RT Journal Article SR Electronic(1) A1 Roy, Samir K. A1 Dey, Susanta K. A1 Raha, Syamal K. A1 Chakrabarty, S. L.YR 1990 T1 Purification and properties of an extracellular endoglucanase from Myceliophthora thermophila D-14 (ATCC 48104) JF Microbiology, VO 136 IS 10 SP 1967 OP 1971 DO https://doi.org/10.1099/00221287-136-10-1967 PB Microbiology Society, SN 1465-2080, AB An extracellular endoglucanase (1,4-β-glucanohydrolase, EC 3.2.1.4) produced by Myceliophthora thermophila D-14 (ATCC 48104) has been purified to homogeneity by ammonium sulphate precipitation and two consecutive ion-exchange chromatographic steps on DEAE-Sephadex A-50 columns. The enzyme was purified 13·8-fold and was homogeneous by analytical PAGE and SDS-PAGE. It has a high apparent M r, of about 100000. The pH and temperature optima for its activity were 4·8 and 65°C respectively. The K m of the purified enzyme for CMC (sodium salt) was 3 mg ml−1. The enzyme displayed low activity toward salicin and p-nitrophenyl β-d-glucoside. The activity was enhanced in the presence of Na+, K+ and Ca2+ but effectively inhibited by Hg2+, Fe2+, Mg2+, Cu2+ and NH4 +. Inhibition studies indicated that the enzyme may be a metalloprotein and/or that it requires metal lons for its optimum activity., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-136-10-1967