Department of Molecular Biology and Microbiology, University of Sheffield, Sheffield S10 2TN, UK.
BMC Microbiol. 2009 Dec 18;9:266. doi: 10.1186/1471-2180-9-266.
Bacterial growth and division requires a core set of essential proteins, several of which are still of unknown function. They are also attractive targets for the development of new antibiotics. YsxC is a member of a family of GTPases highly conserved across eubacteria with a possible ribosome associated function.
Here, we demonstrate by the creation of a conditional lethal mutant that ysxC is apparently essential for growth in S. aureus. To begin to elucidate YsxC function, a translational fusion of YsxC to the CBP-ProteinA tag in the staphylococcal chromosome was made, enabling Tandem Affinity Purification (TAP) of YsxC-interacting partners. These included the ribosomal proteins S2, S10 and L17, as well as the beta' subunit of the RNA polymerase. YsxC was then shown to copurify with ribosomes as an accessory protein specifically localizing to the 50 S subunit. YsxC depletion led to a decrease in the presence of mature ribosomes, indicating a role in ribosome assembly and/or stability in S. aureus.
In this study we demonstrate that YsxC of S. aureus localizes to the ribosomes, is crucial for ribosomal stability and is apparently essential for the life of S. aureus.
细菌的生长和分裂需要一组核心的必需蛋白，其中有几个的功能仍然未知。它们也是开发新抗生素的有吸引力的目标。YsxC 是一种在真细菌中高度保守的 GTPase 家族的成员，可能具有核糖体相关的功能。
在这里，我们通过创建一个条件致死突变体证明了 ysxC 显然是金黄色葡萄球菌生长所必需的。为了开始阐明 YsxC 的功能，我们在金黄色葡萄球菌染色体上构建了 YsxC 与 CBP-ProteinA 标签的翻译融合，从而能够进行 TAP（串联亲和纯化）以分离 YsxC 的相互作用伙伴。这些包括核糖体蛋白 S2、S10 和 L17，以及 RNA 聚合酶的β'亚基。然后证明 YsxC 作为一种辅助蛋白与核糖体共纯化，特异性地定位于 50S 亚基。YsxC 的耗竭导致成熟核糖体的存在减少，表明其在金黄色葡萄球菌的核糖体组装和/或稳定性中起作用。
在这项研究中，我们证明了金黄色葡萄球菌的 YsxC 定位于核糖体，对核糖体的稳定性至关重要，并且显然是金黄色葡萄球菌生命所必需的。
