Bacterial Stress Response Group, Department of Microbiology, School of Natural Sciences, National University of Ireland, Galway, Ireland.
J Appl Microbiol. 2013 Jan;114(1):11-24. doi: 10.1111/j.1365-2672.2012.05434.x. Epub 2012 Sep 27.
Glutamate plays a central role in a wide range of metabolic processes in bacterial cells. This review focuses on the involvement of glutamate in bacterial stress responses. In particular, it reviews the role of glutamate metabolism in response against acid stress and other stresses. The glutamate decarboxylase (GAD) system has been implicated in acid tolerance in several bacterial genera. This system facilitates intracellular pH homoeostasis by consuming protons in a decarboxylation reaction that produces γ-aminobutyrate (GABA) from glutamate. An antiporter system is usually present to couple the uptake of glutamate to the efflux of GABA. Recent insights into the functioning of this system will be discussed. Finally, the intracellular fate of GABA will also be discussed. Many bacteria are capable of metabolizing GABA to succinate via the GABA shunt pathway. The role and regulation of this pathway will be addressed in the review.
谷氨酸在细菌细胞的广泛代谢过程中起着核心作用。本综述重点介绍了谷氨酸在细菌应激反应中的作用。特别是，它综述了谷氨酸代谢在应对酸应激和其他应激中的作用。谷氨酸脱羧酶（GAD）系统已被认为参与了几种细菌属的酸耐受。该系统通过脱羧反应消耗质子，将谷氨酸转化为γ-氨基丁酸（GABA），从而促进细胞内 pH 稳态。通常存在一种转运体系统将谷氨酸的摄取与 GABA 的外排偶联起来。将讨论对该系统功能的最新认识。最后，还将讨论 GABA 的细胞内命运。许多细菌能够通过 GABA 支路途径将 GABA 代谢为琥珀酸。本综述将讨论该途径的作用和调节。
