%0 Journal Article %T Purification and Characterization of a Lipase from Aspergillus niger F044
黑曲霉F044脂肪酶的分离纯化及酶学性质研究 %A SHU Zheng-Yu %A YANG Jiang-Ke %A YAN Yun-Jun %A
舒正玉 %A 杨江科 %A 闫云君 %J 生物工程学报 %D 2007 %I %X A lipase from Aspergillus niger F044 was purified to homogeneity using ammonium sulfate precipitation, dialysis, DEAE-Sepharose Fast Flow anion exchange chromatography and Sephadex G-75 gel filtration chromatography. This purification protocol resulted in a 73.71-fold purification of lipase with 33.99% final yield, and the relative molecular weight of the enzyme was determined to be approximately 35-40kD using SDS-PAGE. The optimum pH and temperature for lipolytic activity of the lipase was 7.0 and 45 degrees C , respectively. It was extremely stable at 60 degrees C and retained 98.70% of its original activity for 30min. The stability declined rapidly as soon as the temperature rose over 65 degrees C . The lipase was highly stable in the pH range from 2.0 to 9.0 for 4h. Ca2+ and Mg2+ ions stimulated lipolytic activity, whereas Mn2+ , Fe2+ and Zn2+ ions caused inhibition. The values of Km and Vmax calculated from the Lineweaver-Burk plot using pNPP as hydrolysis substrate were 7.37mmol/L and 25.91 micromol/(min x mg), respectively. The N-terminal sequence of the lipase was Ser/Glu/His-Val-Ser-Thr-Ser-Thr-Leu-Asp-Glu-Leu-Gln-Leu-Phe-Ala-Gln, which is highly homogeneity with that of lipase, as reported by Torossian. %K Aspergillus niger %K lipase %K purification %K enzyme characterization
黑曲霉 %K 脂肪酶 %K 分离纯化 %K 理化性质 %U http://www.alljournals.cn/get_abstract_url.aspx?pcid=90BA3D13E7F3BC869AC96FB3DA594E3FE34FBF7B8BC0E591&jid=A66E90C274451689E69F6F0291467824&aid=4FA3058F81E99A18&yid=A732AF04DDA03BB3&vid=EA389574707BDED3&iid=CA4FD0336C81A37A&sid=6700D0D256586E73&eid=8C83C265AD318E34&journal_id=1000-3061&journal_name=生物工程学报&referenced_num=7&reference_num=28