Accumulation of ppGpp and ppGp in Staphylococcus aureus 8325-4 following nutrient starvation
Accumulation of ppGpp and ppGp in Staphylococcus aureus 8325-4 following nutrient starvation
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DOI：
10.1046/j.1472-765x.2000.00822.x
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发表时间：
2000-10-01
影响因子：
2.4
通讯作者：
England, RR
中科院分区：
文献类型：
--
作者：
Crosse, AM;Greenway, DLA;England, RR
目的：研究营养剥夺后金黄色葡萄球菌8325-4中高度磷酸化鸟苷酸的积累。通过核苷酸的金黄色葡萄球菌HPLC和无细胞提取物的蛋白质印迹，ppGpp在加入莫匹罗星后或碳剥夺后，当细胞被剥夺异亮氨酸时迅速积累。相比之下，总氨基酸饥饿导致延迟生产的ppGp，这表明，葡萄球菌。与其它真细菌相比，金黄色葡萄球菌对总氨基酸剥夺表现出独特的反应。在所有饥饿条件下观察到细胞内ppGp处于高水平，这表明这种核苷酸与营养限制有关，因此可能参与调节葡萄球菌的严格反应。金黄色。在任何营养限制条件下均未观察到pppGpp。葡萄球菌全细胞提取物的蛋白质印迹分析。金黄色葡萄球菌8325-4，表明抗体RelA和SpoT交叉反应的条件下，检测这些蛋白质在大肠杆菌。金黄色葡萄球菌在营养限制后产生ppGpp和ppGp。免疫学分析表明，葡萄球菌。金黄色葡萄球菌含有RelA和SpoT蛋白，与E.这项研究的意义和影响：这项研究为细菌代谢调节的多样性提供了一个新的例子。
Aim: To investigate the accumulation of highly phosphorylated guanosine nucleotides in Staphylococcus aureus 8325-4 following nutrient deprivation.Methods and Results: Nutrient shiftdown of Staph. aureus HPLC of nucleotides and Western blotting of cell-free extracts, ppGpp rapidly accumulated when cells were deprived of isoleucine following addition of mupirocin, or after carbon deprivation. In contrast, total amino acid starvation led to delayed production of ppGp, which suggests that Staph. aureus exhibits a unique response to total amino acid deprivation compared with other eubacteria. Intracellular ppGp was observed at high levels under all starvation conditions, which suggests that this nucleotide is linked to nutrient limitation and may therefore be involved in regulating the stringent response in Staph. aureus. pppGpp was not observed under any nutrient-limiting condition. Western blot analysis of whole-cell extracts from Staph. aureus 8325-4, showed that antibodies to RelA and SpoT cross-reacted under conditions that detected these proteins in Escherichia coli.Conclusions: Staph. aureus produces ppGpp and ppGp following nutrient limitation. Immunological analysis indicates that Staph. aureus contains RelA and SpoT proteins, similar to those produced by E. coli.Significance and Impact of the Study: This study provides a new example of the diversity of metabolic regulations in bacteria.