摘要
采用含pTrc 99B/leuS2转化子的高表达菌株 ,简便快速地提取、纯化大肠杆菌亮氨酰 tRNA合成酶。对部分稀土离子参与下的氨酰化反应表观稳态动力学性质进行了研究。氨酰化反应所需的Mg2 + 有可能被稀土离子取代 ,脱镁tRNALeu1 与未脱镁tRNALeu1 对ATP和亮氨酸的表观Km 值明显不同。高浓度ATP对脱镁tRNA显示抑制作用 ,说明金属离子是氨酰化反应的底物之一。
Escherichia coli leucyl tRNA synthetase(LeuRS) was overproduced and purified from an overexpression strain. The apparent steady state kinetics of the aminoacylation reaction catalyzed by LeuRS at the participation of some RE 3+ was studied. The results show that Mg 2+ can be substituted by RE 3+ for the aminoacylation reaction. The apparent K m values for ATP and leucine are markedly different between native and Mg 2+ free tRNA Leu 1. At high concentration of ATP, there is inhibition for Mg 2+ free tRNA but not for native tRNA, which indicates that metal ion is one of the substrate of the aminoacylation reaction.
出处
《中国稀土学报》
CAS
CSCD
北大核心
2000年第2期160-164,共5页
Journal of the Chinese Society of Rare Earths
基金
国家教委博士点基金!( 970 0 10 4)
河北省博士基金
中国科学院上海生物化学研究所分子生物学国家重点实验室基金!( 4 0 5 K)
