Song Yang, Zhang Fan, Li Xu, Zang Jianye, Zhang Xuan
Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, Collaborative Innovation Center of Chemistry for Life Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, People's Republic of China.
Acta Crystallogr F Struct Biol Commun. 2015 Aug;71(Pt 8):1038-41. doi: 10.1107/S2053230X15011097. Epub 2015 Jul 28.
SarV, a member of the SarA protein family, is a global transcriptional regulator which has been reported to be involved in the regulation of autolysis in Staphylococcus aureus. In this study, SarV from S. aureus was successfully cloned, expressed, purified and crystallized. X-ray diffraction data were collected to 2.10 Å resolution. The crystals of SarV belonged to the monoclinic space group P21, with unit-cell parameters a = 36.40, b = 119.64, c = 66.80 Å, α = γ = 90, β = 98.75°. The Matthews coefficient and the solvent content were estimated to be 2.57 Å(3) Da(-1) and 52%, respectively, suggesting the presence of four molecules in the asymmetric unit. The results of size-exclusion chromatography (SEC) indicated that S. aureus SarV exists as a homodimer in solution. Unfortunately, the structure cannot be solved by molecular replacement because of the low sequence identity of S. aureus SarV to known structures. Further phase determination by selenomethionine single-wavelength anomalous dispersion (SAD) and the heavy-atom method is in progress.
SarV是SarA蛋白家族的成员，是一种全局转录调节因子，据报道它参与金黄色葡萄球菌自溶的调节。在本研究中，成功克隆、表达、纯化并结晶了来自金黄色葡萄球菌的SarV。收集到分辨率为2.10 Å的X射线衍射数据。SarV晶体属于单斜空间群P21，晶胞参数为a = 36.40、b = 119.64、c = 66.80 Å，α = γ = 90°，β = 98.75°。马修斯系数和溶剂含量估计分别为2.57 ų Da⁻¹和52%，表明不对称单元中存在四个分子。尺寸排阻色谱（SEC）结果表明，金黄色葡萄球菌SarV在溶液中以同型二聚体形式存在。遗憾的是，由于金黄色葡萄球菌SarV与已知结构的序列同一性较低，无法通过分子置换法解析其结构。目前正在通过硒代甲硫氨酸单波长反常散射（SAD）和重原子法进行进一步的相位测定。
