Regulation and consequence of serine catabolism in Streptococcus pyogenes.
Regulation and consequence of serine catabolism in Streptococcus pyogenes.
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化脓性链球菌丝氨酸分解代谢的调节和后果。
DOI：
10.1128/jb.01516-10
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发表时间：
2011
影响因子：
3.2
通讯作者：
Federle,MichaelJ
中科院分区：
文献类型：
--
作者：
LaSarre,Breah;Federle,MichaelJ
革兰氏阳性细菌化脓性链球菌（也称为帕斯脲球菌[GAS]）只存在于人类中，能够引起多种感染。在这里，我们证明了GAS中的丝氨酸分解代谢是由转录调节因子Spy49_0126c控制的。我们将这种调节因子命名为SerR（丝氨酸分解代谢调节因子）。微阵列和转录报告数据显示，SerR作为多个操作子的转录抑制因子，包括slorandsdhba。纯化的重组SerR结合到slorandsdhb的启动子上，表明这种调控是直接的。当菌株在确定的培养基中生长时，除非提供额外的丝氨酸，否则删除serr会导致突变体的培养产量低于野生型，这表明丝氨酸代谢的调节对于最大化细菌生长很重要。在ΔserRmutant背景下删除slororsdhbin可使生长恢复到野生型水平，这表明这两个操作子都在丝氨酸分解代谢中起作用。虽然有报道将loro的功能与链溶素O的表达联系起来，但放射性标记丝氨酸的转运实验表明，loro操纵子是快速获取丝氨酸所必需的，这表明该操纵子在氨基酸代谢中的新作用。
The Gram-positive bacterium Streptococcus pyogenes (also calledgroupAStreptococcus [GAS]), is found strictly in humans and is capable of causing a wide variety of infections. Here we demonstrate that serine catabolism in GAS is controlled by the transcriptional regulator Spy49_0126c. We have designated this regulator SerR (forserine catabolismregulator). Microarray and transcriptional reporter data show that SerR acts as a transcriptional repressor of multiple operons, includingsloRandsdhBA. Purified recombinant SerR binds to the promoters of bothsloRandsdhB, demonstrating that this regulation is direct. Deletion ofserRresults in a lower culture yield of the mutant than of the wild type when the strains are grown in defined medium unless additional serine is provided, suggesting that regulation of serine metabolism is important for maximizing bacterial growth. Deletion ofsloRorsdhBin the ΔserRmutant background restores growth to wild-type levels, suggesting that both operons have roles in serine catabolism. While reports have linkedsloRfunction to streptolysin O expression, transport experiments with radiolabeledl-serine reveal that thesloRoperon is required for rapid acquisition of serine, suggesting a novel role for this operon in amino acid metabolism.