Nakayama Yoshitaka
Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia.
St Vincent's Clinical School, Faculty of Medicine, The University of New South Wales, Darlinghurst, NSW 2010, Australia.
Microorganisms. 2021 Jan 19;9(1):201. doi: 10.3390/microorganisms9010201.
After the discovery of from avian feces-contaminated soil, its enigmatic L-glutamate secretion by corynebacterial MscCG-type mechanosensitive channels has been utilized for industrial monosodium glutamate production. Bacterial mechanosensitive channels are activated directly by increased membrane tension upon hypoosmotic downshock; thus; the physiological significance of the corynebacterial L-glutamate secretion has been considered as adjusting turgor pressure by releasing cytoplasmic solutes. In this review, we present information that corynebacterial mechanosensitive channels have been evolutionally specialized as carriers to secrete L-glutamate into the surrounding environment in their habitats rather than osmotic safety valves. The lipid modulation activation of MscCG channels in L-glutamate production can be explained by the "Force-From-Lipids" and "Force-From-Tethers" mechanosensing paradigms and differs significantly from mechanical activation upon hypoosmotic shock. The review also provides information on the search for evidence that was originally a gut bacterium in the avian host with the aim of understanding the physiological roles of corynebacterial mechanosensing. is able to secrete L-glutamate by mechanosensitive channels in the gut microbiota and help the host brain function via the microbiota-gut-brain axis.
从受禽粪污染的土壤中发现后，棒状杆菌的MscCG型机械敏感通道神秘的L-谷氨酸分泌已被用于工业味精生产。细菌机械敏感通道在低渗性休克时通过增加的膜张力直接激活；因此，棒状杆菌L-谷氨酸分泌的生理意义被认为是通过释放细胞质溶质来调节膨压。在这篇综述中，我们提供的信息表明，棒状杆菌机械敏感通道已进化为专门的载体，将L-谷氨酸分泌到其栖息地的周围环境中，而不是渗透安全阀。L-谷氨酸生产中MscCG通道的脂质调节激活可以用“来自脂质的力”和“来自系链的力”机械传感范式来解释，并且与低渗休克时的机械激活有显著差异。该综述还提供了有关寻找证据的信息，即最初是禽类宿主中的肠道细菌，目的是了解棒状杆菌机械传感的生理作用。能够通过肠道微生物群中的机械敏感通道分泌L-谷氨酸，并通过微生物群-肠道-脑轴帮助宿主大脑功能。
