PROCESSING OF THE INITIATION METHIONINE FROM PROTEINS - PROPERTIES OF THE ESCHERICHIA-COLI METHIONINE AMINOPEPTIDASE AND ITS GENE STRUCTURE
PROCESSING OF THE INITIATION METHIONINE FROM PROTEINS - PROPERTIES OF THE ESCHERICHIA-COLI METHIONINE AMINOPEPTIDASE AND ITS GENE STRUCTURE
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DOI：
10.1128/jb.169.2.751-757.1987
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发表时间：
1987-02-01
影响因子：
3.2
通讯作者：
CHANG, S
中科院分区：
文献类型：
--
作者：
BENBASSAT, A;BAUER, K;CHANG, S
蛋氨酸氨基肽酶（Methionine aminopeptidase， MAP）催化蛋白质中氨基末端蛋氨酸的去除。克隆了编码该酶的大肠杆菌图谱基因；它由264个密码子组成，编码一个29333道尔顿的单体酶。纯化酶体外分析表明，MAP是一种对氨基端蛋氨酸具有绝对特异性的金属寡肽酶。重组蛋白白介素-2 （Met-Ala-Pro-IL-2）和蓖麻毒素A （Met-Ile-Phe-ricin A）的氨基末端的蛋氨酸残基可以在体外用纯化的MAP酶去除，也可以在体内用MAP高产菌株去除。体外对大肠杆菌MAP的底物偏好分析表明，起始蛋氨酸附近的残基可以显著影响蛋氨酸的裂解过程。总的来说，这一结论与基于对已知细胞内蛋白氨基末端序列的分析推断出的酶的特异性是一致的（S. Tsunasawa， J. W. Stewart， F. Sherman， J. Biol）。化学。260:5382-5391,1985)。
Methionine aminopeptidase (MAP) catalyzes the removal of amino-terminal methionine from proteins. The Escherichia coli map gene encoding this enzyme was cloned; it consists of 264 codons and encodes a monomeric enzyme of 29,333 daltons. In vitro analyses with purified enzyme indicated that MAP is a metallooligopeptidase with absolute specificity for the amino-terminal methionine. The methionine residues from the amino-terminal end of the recombinant proteins interleukin-2 (Met-Ala-Pro-IL-2) and ricin A (Met-Ile-Phe-ricin A) could be removed either in vitro with purified MAP enzyme or in vivo in MAP-hyperproducing strains of E. coli. In vitro analyses of the substrate preference of the E. coli MAP indicated that the residues adjacent to the initiation methionine could significantly influence the methionine cleavage process. This concluson is consistent, in general, with the deduced specificity of the enzyme based on the analysis of known amino-terminal sequences of intracellular proteins (S. Tsunasawa, J. W. Stewart, and F. Sherman, J. Biol. Chem. 260: 5382-5391, 1985).