重组大鼠和小鼠RT6 T细胞单（ADP-核糖基）转移酶在大肠杆菌中的表达及比较分析

Expression and comparative analysis of recombinant rat and mouse RT6 T cell mono(ADP-ribosyl)transferases in E. coli.

作者信息

Karsten S, Schröder J, da Silva C, Kahlke D, Thiele H G, Koch-Noite F, Haag F

机构信息

Department of Physiological Chemistry, Hamburg University, Germany.

出版信息

Adv Exp Med Biol. 1997;419:175-80. doi: 10.1007/978-1-4419-8632-0_21.

DOI:10.1007/978-1-4419-8632-0_21

PMID:9193651

Abstract

Recombinant RT6 proteins of rat and mouse were analyzed for NAD-metabolizing, i.e. mono(ADP-ribosyl)transferase, NAD-glycohydrolase (NADase) and ADP-ribosyl cyclase activities. The results reveal surprising intra- as well as inter-species differences in enzyme activities. While mouse Rt6 proteins were found to be strong arginine-specific transferases, but comparatively weak NADases, the opposite held true for rat RT6, for which transferase activity could only be detected in the form of arginine-specific auto-ADP-ribosylation, displayed by RT6.2 but not by RT6.1. NADase activity of rat RT6 was not accompanied by production of cyclic ADPR (cADPR). Rat RT6 gained potent arginine-specific transferase activity by exchange of a single amino acid for the corresponding residue of the mouse proteins.

摘要

对大鼠和小鼠的重组RT6蛋白进行了NAD代谢分析，即单（ADP-核糖基）转移酶、NAD糖水解酶（NADase）和ADP-核糖基环化酶活性分析。结果揭示了酶活性在种内和种间存在惊人的差异。虽然发现小鼠Rt6蛋白是强精氨酸特异性转移酶，但相对较弱的NADases，大鼠RT6则相反，其转移酶活性仅以精氨酸特异性自身ADP-核糖基化的形式检测到，由RT6.2而非RT6.1表现。大鼠RT6的NADase活性并未伴随环化ADPR（cADPR）的产生。通过将单个氨基酸替换为小鼠蛋白的相应残基，大鼠RT6获得了强大的精氨酸特异性转移酶活性。