Ryan Brooke E, Mike Laura A
Medical Microbiology and Immunology, University of Toledo, Toledo, Ohio, USA.
Department of Medicine, Division of Infectious Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
Infect Immun. 2025 Aug 12;93(8):e0061224. doi: 10.1128/iai.00612-24. Epub 2025 Jul 3.
Nutrient availability shapes the course of infection. Arginine, a conditionally essential amino acid, plays a crucial role in both host immune defense and pathogen metabolism. As a precursor for nitric oxide production, arginine supports immune functions in multiple immune cell types to control infections. However, it also serves as a signal for pathogens that promotes bacterial survival and growth. A plethora of recent studies have shown that arginine functions not only as a metabolic substrate but also as a key environmental cue that can alter cyclic diguanylate levels. Arginine availability regulates multiple bacterial processes in both Gram-positive and Gram-negative species including toxin production, biofilm formation, Type III secretion system, swarming, persistence, and immune evasion. In this way, arginine levels can shape how pathogens behave within the host environment. This review examines how fluctuations in arginine levels across different host niches influence microbial pathogenesis and highlights the complex interplay between arginine availability and bacterial behavior. Understanding the role of arginine in host-pathogen interactions may provide new therapeutic strategies to combat infections by targeting bacterial responses to this crucial nutrient.
营养物质的可利用性决定了感染的进程。精氨酸是一种条件必需氨基酸，在宿主免疫防御和病原体代谢中都起着关键作用。作为一氧化氮产生的前体，精氨酸支持多种免疫细胞类型的免疫功能以控制感染。然而，它也是病原体的一种信号，可促进细菌的存活和生长。最近大量研究表明，精氨酸不仅作为一种代谢底物发挥作用，还作为一种关键的环境信号，可以改变环二鸟苷酸水平。精氨酸的可利用性调节革兰氏阳性菌和革兰氏阴性菌的多种细菌过程，包括毒素产生、生物膜形成、III型分泌系统、群体运动、持续存在和免疫逃避。通过这种方式，精氨酸水平可以塑造病原体在宿主环境中的行为方式。这篇综述探讨了不同宿主生态位中精氨酸水平的波动如何影响微生物发病机制，并强调了精氨酸可利用性与细菌行为之间的复杂相互作用。了解精氨酸在宿主-病原体相互作用中的作用可能会提供新的治疗策略，通过针对细菌对这种关键营养素的反应来对抗感染。
