摘要
通过参Ｕ法定点突变产生了ＴａｑＤＮＡ聚合酶Ｎ端分别缺失３个，２３５个，２８７个和４４３个氨基酸的４个缺失体，利用Ｂａｌ－３１连续缺失法产生了ＴａｑＤＮＡ聚合酶的Ｃ端分别缺失了２个、１６个、２９个、３２个、３４个氨基酸的５个缺失体．经ＤＮＡ聚合酶活性测定表明Ｎ端缺失３个，２３５个，２８７个氨基酸后活力和完整的Ｔａｑ相近，而缺失４４３个氨基酸后则失去了ＤＮＡ聚合酶活力；Ｃ端的５个缺失体都失去了ＤＮＡ聚合酶活性．据此ＴａｑＤＮＡ聚合酶的功能区域被定位在２８７～８３２氨基酸之间．
Four truncators with deletion of 3,235,287 and 443 amino acids at N terminus of Taq DNA polymerase were obtained through ural mediated site direct mutagenesis.Five truncators with deletion of 2,16,29,32 and 34 amino acids at C terminus were obtained through continuous deletion with Bal 31 nuclease.Their DNA polymerase activity was measured.It was found that truncators with deletion of 3,235 and 287 amino acids at N terminus maintained the DNA polymerase activity and their specific activity was identical to that of native Taq DNA polymerase while other truncators with deletion at N terminus or C terminus lost their DNA polymerase activity.Based on these,the domain responsible for the DNA polymerase activity of Taq DNA polymerase was located between 287 amino acid and 832 amino acid.
出处
《中国生物化学与分子生物学报》
CAS
CSCD
1999年第3期432-435,共4页
Chinese Journal of Biochemistry and Molecular Biology
基金
国家自然科学基金
