Braeken Kristien, Moris Martine, Daniels Ruth, Vanderleyden Jos, Michiels Jan
Centre of Microbial and Plant Genetics, Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium.
Trends Microbiol. 2006 Jan;14(1):45-54. doi: 10.1016/j.tim.2005.11.006. Epub 2005 Dec 15.
A hyperphosphorylated guanosine nucleotide, (p)ppGpp, was initially identified as the effector molecule responsible for the stringent response in Escherichia coli. However, a rapidly growing number of reports proves that (p)ppGpp-mediated regulation is conserved in many bacteria and even in plants. It is now clear that (p)ppGpp acts as a global regulator during physiological adaptation of the organism to a plethora of environmental conditions. Adaptation is not only essential for surviving periods of stress and nutrient exhaustion but also for the interaction of bacteria with their eukaryotic host, as observed during pathogenesis and symbiosis, and for bacterial multicellular behaviour. Recently, there have been several new discoveries about the effects of (p)ppGpp levels, balanced by RelA-SpoT homologue proteins, in diverse organisms.
一种超磷酸化鸟苷核苷酸，（p）ppGpp，最初被鉴定为负责大肠杆菌严谨反应的效应分子。然而，越来越多的报告证明，（p）ppGpp介导的调控在许多细菌甚至植物中都保守存在。现在很清楚，（p）ppGpp在生物体对多种环境条件的生理适应过程中作为一种全局调节因子发挥作用。适应不仅对于在应激和营养耗尽时期的存活至关重要，而且对于细菌与真核宿主的相互作用（如在发病机制和共生过程中所观察到的）以及细菌的多细胞行为也至关重要。最近，关于由RelA-SpoT同源蛋白平衡的（p）ppGpp水平在不同生物体中的作用有了一些新发现。
