Characterization of a flavoprotein:soluble pyridine nucleotide transhydrogenase from Salmonella typhimurium 14028
作者单位：Institute of Molecular Biology and BiotechnologyAnhui Normal University
会议名称：《第八届全国医学生物化学与分子生物学第五届全国临床应用生物化学与分子生物学2013华东六省一市生物化学与分子生物学联合学术研讨会》
会议日期：2013年
学科分类：1007[医学-药学(可授医学、理学学位)] 100705[医学-微生物与生化药学] 1001[医学-基础医学(可授医学、理学学位)] 100103[医学-病原生物学] 10[医学]
关 键 词：soluble pyridine nucleotide transhydrogenase Salmonella typhimurium biochemical characterization cofactor regeneration
摘 要：Soluble pyridine nucleotide transhydrogenase(STH or UdhA) was widely utilized in the industrial application through genetic and metabolic *** the gene encoding Salmonella typhimurium 14028 STH(StSTH) was cloned and expressed in Escherichia coli Rosetta(DE3).The molecular mass of the purified StSTH enzyme was estimated to be 540 kDa by gel filtration chromatography,suggesting that the enzyme is a *** recombinant StSTH exhibited maximum activity at pH 7.2 and 32 ℃.The half-life of StSTH was 5 hours at50 ℃ and 30 min at 60 ℃.The enzyme had high storage stability and retained over 80% of its initial activity after stored for 40 days at 4 ℃.The apparent kinetic parameters,K and V for thio-NAD,were 168.9 μM and 43.0 μM·min,and K,V and K for NADPH were 69.5 μM,36.3 μM·min and 607.3 μ*** activity of StSTH was strongly inhibited by metal ions(such as K,Li,Ca,Mn,Co,Zn,Ni and Cu),and stimulated by 2 mM ATP,ADP and AMP,*** characteristics of StSTH make it an attractive alternative to many industrial applications such as cofactor regeneration.