Infection Discovery, AstraZeneca R&D Boston, 35 Gatehouse Drive, Waltham, MA 02451, USA.
Microb Biotechnol. 2008 Sep;1(5):345-60. doi: 10.1111/j.1751-7915.2008.00031.x. Epub 2008 May 11.
The bacterial cell wall is a highly cross-linked polymeric structure consisting of repeating peptidoglycan units, each of which contains a novel pentapeptide substitution which is cross-linked through transpeptidation. The incorporation of D-glutamate as the second residue is strictly conserved across the bacterial kingdom. Glutamate racemase, a member of the cofactor-independent, two-thiol-based family of amino acid racemases, has been implicated in the production and maintenance of sufficient d-glutamate pool levels required for growth. The subject of over four decades of research, it is now evident that the enzyme is conserved and essential for growth across the bacterial kingdom and has a conserved overall topology and active site architecture; however, several different mechanisms of regulation have been observed. These traits have recently been targeted in the discovery of both narrow and broad spectrum inhibitors. This review outlines the biological history of this enzyme, the recent biochemical and structural characterization of isozymes from a wide range of species and developments in the identification of inhibitors that target the enzyme as possible therapeutic agents.
细菌细胞壁是一种高度交联的聚合结构,由重复的肽聚糖单元组成,每个单元都含有一个新的五肽取代基,通过转肽作用交联。在整个细菌界,D-谷氨酸作为第二个残基的掺入是严格保守的。谷氨酸消旋酶是一种不依赖辅因子的、基于两个巯基的氨基酸消旋酶家族的成员,它与生长所需的足够的 d-谷氨酸池水平的产生和维持有关。作为四十多年研究的主题,现在很明显,该酶在整个细菌界的生长中是保守的和必不可少的,并且具有保守的整体拓扑结构和活性位点结构;然而,已经观察到几种不同的调节机制。这些特征最近已成为发现窄谱和广谱抑制剂的目标。这篇综述概述了该酶的生物学历史、来自广泛物种的同工酶的最新生化和结构特征,以及鉴定作为潜在治疗剂的靶向该酶的抑制剂的进展。