水产学报2017，Vol.41Issue(6)：845-853,9.DOI:10.11964/jfc.20161210642
金乌贼肌肉中三甲胺脱甲基酶的分离纯化及酶学性质
Purification and enzymatic properties of TMAOase from muscles of Sepia esculenta
摘要
Abstract
In order to extract and purify TMAOase, acetate buffer made of NaCl (0.1 mol/L) and Tris-CH3COOH (pH 7.0, 20 mmol/L) was used to extract from the muscles of cuttlefish.After the process of acid, alkali, dialysis and concentrated treatment, the extract was further purified by DEAE-52 Sephacel and Sephacryl S-300 chromatography. The enzymatic properties of TMAOase were also studied. The results revealed that the enzyme purified by Sephacryl S-300 was 209.54 times purer than the crude enzyme. The optimum temperature of the curde and purified enzyme was 55 and 50 ℃, respectively. Moreover, their thermal stability decreased significantly over this temperature. As the temperature reached 80 ℃, crude enzyme still retaimed 21.9% of its activity. Whereas purified enzyme lost its activity totally. The optimum pH of the purified enzyme was 7.0, which stayed well at this pH, but decreased in acidic and alkaline conditions. As the pH increased to 9.0,especially, the activity of crude and pure enzyme reduced to 60.7% and 20.5%, respectively. The Km of TMAOase measured by Lineweaver-Burk double reciprocal mapping method was 22.8 mmol/L. The purity of the obtained TMAOase was proved by SDS-PAGE, with a molecular weight of 21.3 ku. Chemicals of citric acid and CaCl2 remarkably promoted the activity of the enzyme , while H2O2 and Na2S significantly inhibited TMAOase activity.关键词
金乌贼/肌肉/三甲胺脱甲基酶/纯化/酶学性质Key words
Sepia esculenta/muscle/TMAOase/purification/enzymatic properties分类
农业科技引用本文复制引用
金洋,薛张芝,张洪超,宋正规,朱仁义,步婷婷,李和生..金乌贼肌肉中三甲胺脱甲基酶的分离纯化及酶学性质[J].水产学报,2017,41(6):845-853,9.基金项目
浙江省重大科技专项(2009C03017-3) （2009C03017-3）
"水产"浙江省重中之重学科开放基金(xkzsc1523) （xkzsc1523）
宁波市自然科学基金(013A610156) Major Scientific and Technological Projects in Zhejiang Province (2009C03017-3) （013A610156）
"Aquatic Products" in Zhejiang Province Top Priority Disciplines Open Fund (xkzsc1523) （xkzsc1523）
Ningbo Natural Fund Project (013A610156) （013A610156）
