Structural and Mechanistic Insights into NDM-1 Catalyzed Hydrolysis of Cephalosporins
Structural and Mechanistic Insights into NDM-1 Catalyzed Hydrolysis of Cephalosporins
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NDM-1 催化头孢菌素水解的结构和机制见解
DOI：
10.1021/ja508388e
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发表时间：
2014-10-22
影响因子：
15
通讯作者：
Liu, Wei
中科院分区：
文献类型：
--
作者：
Feng, Han;Ding, Jingjin;Liu, Wei
头孢菌素构成临床上用作抗微生物药物的一大类β-内酰胺抗生素。新型Dehli金属β-内酰胺酶（NDM-1）对人类健康构成了全球性威胁，因为它赋予细菌病原体对几乎所有β-内酰胺类药物（包括青霉素类、头孢菌素类和碳青霉烯类）的耐药性。在这里，我们报告的第一个晶体结构的NDM-1在复杂的头孢呋辛和头孢氨苄，以及NMR光谱监测头孢呋辛和头孢克肟水解NDM-1催化。令人惊讶的是，在1.3和2.0 A下测定的两种晶体结构中都捕获了头孢菌素中间体。这些结果提供了有关头孢菌素水解的机制和途径的详细信息。我们还提出了晶体结构和酶测定的D124 N突变体，这表明，D124最有可能发挥更多的结构比催化作用。
Cephalosporins constitute a large class of beta-lactam antibiotics clinically used as antimicrobial drugs. New Dehli metallo-beta-lactamase (NDM-1) poses a global threat to human health as it confers on bacterial pathogen resistance to almost all beta-lactams, including penicillins, cephalosporins, and carbapenems. Here we report the first crystal structures of NDM-1 in complex with cefuroxime and cephalexin, as well as NMR spectra monitoring cefuroxime and cefixime hydrolysis catalyzed by NDM-1. Surprisingly, cephalosporoate intermediates were captured in both crystal structures determined at 1.3 and 2.0 A. These results provide detailed information concerning the mechanism and pathways of cephalosporin hydrolysis. We also present the crystal structure and enzyme assays of a D124N mutant, which reveals that D124 most likely plays a more structural than catalytic role.