摘要
采用硫酸铵分级沉淀和柱层析方法 ,从黑麦草叶片中分离得到纯的铜锌超氧化物岐化酶。经鉴定该酶是Cu·Zn SOD。测得其分子量约为 3 2 1 0 0 ,亚基分子量约 1 5 90 0。该酶的N 末端为丙氨酸 ,其紫外光区最大吸收峰在 2 5 4nm。该酶的热稳定性较好 ,65℃保温 1h仍保留活性 2 7%。氨基酸组成分析表明 ,黑麦草SOD由 2 1 2个氨基酸残基组成 ,而且不含色氨酸。
Superoxide dismutase(SOD) separated and extracted from ryegrass leaves( Lolium perenneperennial ) was purified by fraction precipitation by ammonium sulfate and column chromatography. The purified enzyme is found to be a copper/zinc superoxide dismutase as assayed by its sensitivity to KCN and H 2 O 2 . Electrophoretic analysis indicated that the enzyme contains two homogenous subunits with molecular weight of 15 900 with N terminal being alanine and maximum ultraviolet absorption at 254 nm. The SOD from ryegrass leaves is thermal stable with activity loss of 27% at 65 ℃ for an hour. Quantitative analysis of amino acids revealed that this protein was composed of 212 amino acids and lack of tryptophan.
出处
《应用化学》
CAS
CSCD
北大核心
2003年第5期474-478,共5页
Chinese Journal of Applied Chemistry
基金
重庆市科委攻关项目 ( 2 0 0 1 18 12 )
