Purification and characterization of sortase, the transpeptidase that cleaves surface proteins of Staphylococcus aureus at the LPXTG motif
Purification and characterization of sortase, the transpeptidase that cleaves surface proteins of Staphylococcus aureus at the LPXTG motif
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DOI：
10.1073/pnas.96.22.12424
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发表时间：
1999-10-26
影响因子：
11.1
通讯作者：
Schneewind, O
中科院分区：
文献类型：
--
作者：
Ton-That, H;Liu, G;Schneewind, O
金黄色葡萄球菌的表面蛋白通过分选酶连接到细菌细胞壁，分选酶是一种在LPXTG基序的苏氨酸处切割多肽的酶。葡萄球菌经羟胺处理后可释放表面蛋白，形成苏氨酸异羟肟酸盐。葡萄球菌提取物以及纯化的分选酶催化具有LPXTG基序的肽的羟氨解，该反应可以用巯基修饰试剂抑制。用丙氨酸替换分选酶184位的单个保守半胱氨酸消除了酶活性。因此，分选酶似乎通过转肽反应催化表面蛋白锚定，所述转肽反应捕获裂解的多肽作为硫酯酶中间体。
Surface proteins of Staphylococcus aureus are linked to the bacterial cell wall by sortase, an enzyme that cleaves polypeptides at the threonine of the LPXTG motif. Surface proteins can be released from staphylococci by treatment with hydroxylamine, resulting in the formation of threonine hydroxamate. Staphylococcal extracts, as well as purified sortase, catalyze the hydroxylaminolysis of peptides bearing an LPXTG motif, a reaction that can be inhibited with sulfhydryl-modifying reagents. Replacement of the single conserved cysteine at position 184 of sortase with alanine abolishes enzyme activity. Thus, sortase appears to catalyze surface-protein anchoring by means of a transpeptidation reaction that captures cleaved polypeptides as thioester enzyme intermediates.