PSS定点突变及酶活研究

磷脂酰丝氨酸可在磷脂酰丝氨酸合成酶(PSS)催化下由磷脂酰胆碱和L-丝氨酸生成。通过生物信息学手段对磷脂酰丝氨酸合成酶蛋白质结构进行解析和研究分析,获得2个可突变位点F139和P272,通过Overlap PCR法进行定点突变,测定突变序列,并进行酶活测定。结果显示,PSS位点F139突变为L139、M139,位点P272突变为A272,能提高酶活力,说明蛋白质结构解析结合氨基酸定点突变技术,可以改善重组酶的活力。

Designatted Mutation of Phosphatidylserine Synthetase(PSS) and Its Enzymatic Activity

Phosphatidylserine can be produced via catalyzing phosphatidylcholine（ PC） and L-serine by phosphatidylserine synthetase（ PSS）. The protein structure of PPS was analyzed and studied by means of bioinformatics,and obtained 2 mutable sites F139 and P272 and carry out designated mutation with overlap PCR,and determined the mutation sequences,and carried out enzymatic activity tests. The results showed that the mutation of F139 site of PPS into L139,M139,and P272 site into A272 could enhance the enzymatic activity,indicating the technique of analyzing protein structure combined with amino acid designated mutation could promote the acitivity of the recominant enzyme.