蛋壳内膜分解菌所产蛋白酶的纯化及其N-末端氨基酸序列测定

Purification and N-terminal Amino Acid Sequencing of the ESM Protease Isolated from an Eggshell Mem-brane-degrading Bacteria

从土壤中分离得到的1株产蛋壳内膜分解酶(ESMprotease)的铜绿假单胞菌(Pseudomonasaeruginosa)。通过对其发酵液进行饱和硫酸铵盐析,二次离子交换层析得到蛋壳内膜分解活性达到304.5U/mg的目标蛋白,SDS-PAGE电泳显示该酶分子量约为32kD,通过测定其N-末端15个氨基酸残基为:Ala、Glu、Ala、Gly、Gly、Val、Ala、Gly、Lys、Glu、Asp、Ala、Ala、Glu和Leu。

A strain producing eggshell membrane protease （ESM protease） was isolated from the soil and identified as Pseudomonas aeruginosa. The enzyme isolated from the fermentation liquid of this strain and purified by ammonium sulfate precipitation, quadratic anion-exchange chromatography exhibited eggshell membrane degrading activity of 304.5 U/mg. By SDS-PAGE, the protein molecular mass is 32 kD. The N-terminal amino acid sequence of this protease is： Ala, Glu, Ala, Gly, Gly, Val, Ala, Gly, Lys, Glu, Asp, Ala, Ala, Glu, Leu.