Biomedical Sciences Program, Old Dominion University, Norfolk, Virginia, 23529, USA.
Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, Virginia, 23529, USA.
Microbiology (Reading). 2024 Jul;170(7). doi: 10.1099/mic.0.001479.
The bacterial stringent response (SR) is a conserved transcriptional reprogramming pathway mediated by the nucleotide signalling alarmones, (pp)pGpp. The SR has been implicated in antibiotic survival in , a biofilm- and spore-forming pathogen that causes resilient, highly recurrent infections. The role of the SR in other processes and the effectors by which it regulates physiology are unknown. RelQ is a clostridial alarmone synthetase. Deletion of dysregulates growth in unstressed conditions, affects susceptibility to antibiotic and oxidative stressors and drastically reduces biofilm formation. While wild-type displays increased biofilm formation in the presence of sublethal stress, the Δ strain cannot upregulate biofilm production in response to stress. Deletion of slows spore accumulation in planktonic cultures but accelerates it in biofilms. This work establishes biofilm formation and spore accumulation as alarmone-mediated processes in and reveals the importance of RelQ in stress-induced biofilm regulation.
细菌紧张反应 (SR) 是一种保守的转录重编程途径，由核苷酸信号警报素 (pp)Gpp 介导。SR 被认为与抗生素在 中的生存能力有关， 是一种生物膜和孢子形成的病原体，会导致持久且高度复发的 感染。SR 在其他过程中的作用以及它调节 生理学的效应物尚不清楚。RelQ 是一种梭状芽胞杆菌警报素合成酶。 缺失会导致未受应激条件下的生长失调，影响对抗生素和氧化应激物的敏感性，并大大降低生物膜形成。虽然野生型 在亚致死应激存在下显示出增加的生物膜形成，但 Δ 菌株不能响应应激而上调生物膜的产生。 缺失会减缓浮游培养物中孢子的积累，但会加速生物膜中的积累。这项工作确立了生物膜形成和孢子积累是 中的警报素介导的过程，并揭示了 RelQ 在应激诱导的生物膜调节中的重要性。
