丝氨酸
活动站点
化学
抗生素
细菌
生物化学
立体化学
酰化
微生物学
酶
生物
催化作用
遗传学
作者
Parveen Salahuddin,Amit Kumar,Asad U. Khan
出处
期刊:Current Protein & Peptide Science
[Bentham Science]
日期:2017-12-18
卷期号:19 (2)
被引量:23
标识
DOI:10.2174/0929866524666170724160623
摘要
Antibiotic resistance in gram-negative bacteria has emerged as a major health threat that occurs because these bacteria actively produce β-lactamases responsible for the inactivation of β-lactam antibiotics. The first β lactamase was reported in E. coli back in 1940, before the release of the first antibiotic penicillin in clinical settings. Later on, large numbers of β-lactamases have been discovered in Gram-positive, Gram-negative bacteria as well as mycobacteria. Currently, numerous three-dimensional structures of serine and metallo-β-lactamases have been solved. The serine β-lactamases essentially consist of two structural domains (an all α and an α/β domain) and the active site is located at the groove between the two domains. The catalysis of serine β-lactamase proceeds via acylation and deacylation reactions. The three dimensional structure of metallo-β-lactamases displayed a common four layer “αβ/βα” motif, with a central “ββ”- sandwich by Zn2+ ion(s), and two α-helices are located on the either side. The active site of metallo-β-lactamases contain either 1 or 2 Zn2+ ions, which is coordinated to metal ligating amino acids and polarized water molecule(s) necessary for the hydrolysis of β-lactam antibiotics. Keeping the above views in mind, in this review we have shed light on the current knowledge of the structures and mechanisms of catalysis of serine and metallo-β-lactamases. Moreover, mutational studies on β-lactamases highlight the importance of the active site residues and residues in the vicinity to the active site pocket in the catalysis. To combat bacterial infections more effeciently novel inhibitors of β-lactamase in combination with antibiotics have been used which also form the theme of the review. Keywords: Serine-β-lactamase, metallo-β-lactamase, β-lactam antibiotics, acylation reaction, deacylation reaction, structure of β-lactamases, catalytic mechanism of β-lactamases, inhibitors of β-lactamases.
科研通智能强力驱动
Strongly Powered by AbleSci AI