小鼠Mx1蛋白相关GTP酶的酶学特性

Enzymatic properties of the mouse Mx1 protein-associated GTPase.

作者信息

Nakayama M, Nagata K, Ishihama A

机构信息

Department of Molecular Genetics, National Institute of Genetics, Shizuoka, Japan.

出版信息

Virus Res. 1992 Mar;22(3):227-34. doi: 10.1016/0168-1702(92)90054-d.

DOI:10.1016/0168-1702(92)90054-d

PMID:1626418

Abstract

Murine Mx1 protein, an interferon-inducible nuclear protein present in inbred mouse Mx+ strains, confers resistance to influenza virus infection. The purified Mx1 protein was found to carry the activities of both GTPase and GTP-binding. Enzymatic properties of the Mx1-associated GTPase were examined using the Mx1 protein purified from Escherichia coli expressing Mx1 cDNA. The Mx1 protein exhibited a substrate preference for GTP. The Vmax of ATP hydrolysis was about 7.6% the rate of GTP hydrolysis. The hydrolysis of CTP and UTP was virtually negligible. The Km for GTP hydrolysis was 667 microM and the rate was 13.8 mol GTP hydrolysis per min per mol Mx1 protein. The enzymatic properties of Mx1 protein-associated GTPase were compared with those of the GTPase super-gene family and the Mx-related family.

摘要

小鼠Mx1蛋白是一种存在于近交系Mx +小鼠品系中的干扰素诱导核蛋白，可赋予对流感病毒感染的抗性。发现纯化的Mx1蛋白具有GTP酶和GTP结合活性。使用从表达Mx1 cDNA的大肠杆菌中纯化的Mx1蛋白研究了与Mx1相关的GTP酶的酶学性质。Mx1蛋白对GTP表现出底物偏好性。ATP水解的Vmax约为GTP水解速率的7.6%。CTP和UTP的水解几乎可以忽略不计。GTP水解的Km为667 microM，速率为每摩尔Mx1蛋白每分钟水解13.8摩尔GTP。将Mx1蛋白相关GTP酶的酶学性质与GTP酶超基因家族和Mx相关家族的酶学性质进行了比较。