Crystal structure of recombinant native SDF-1α with additional mutagenesis studies:: An attempt at a more comprehensive interpretation of accumulated structure-activity relationship data
Crystal structure of recombinant native SDF-1α with additional mutagenesis studies:: An attempt at a more comprehensive interpretation of accumulated structure-activity relationship data
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DOI：
10.1089/10799900050116390
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发表时间：
2000-08-01
影响因子：
2.3
通讯作者：
Mitsui, Y
中科院分区：
文献类型：
--
作者：
Ohnishi, Y;Senda, T;Mitsui, Y
用仙台病毒表达载体系统表达的重组天然基质细胞衍生因子-1 α（SDF-1 α）的晶体结构（1型和2型）已通过X射线晶体学在2.0埃分辨率下测定。晶型1的晶体与先前SDF-1 α的合成[N33 A]突变体的晶体结构分析中使用的晶体几乎同晶（Dealwis，C.，等人，Proc. Natl. Acad. Sci. USA 1998;95，6941-6946）。然而，目前的结构分析导致相当好的细化统计，揭示了错误的N-末端残基的结构分配在以前的报告。比较的解决方案的结构，如先前确定的核磁共振（NMR）光谱，和本结构，在不对称单元中的两个单体，揭示了几个局部构象差异。对所谓RFFESH基序中每个残基的丙氨酸扫描诱变研究表明，只有第一个残基Arg 12在增强受体结合（和连续激活）方面有效。一个新的概念，Arg 8和Arg 12之间的空间限制是有利的（如果不是至关重要的）保留SDF活动似乎更一致地解释了迄今为止积累的结构-活性关系数据。四个指导原则，可能是有用的设计有效的治疗化合物干扰HIV-1感染，通过竞争在CXCR 4辅助受体。
Crystal structures, forms 1 and 2, of recombinant native stromal cell-derived factor-1 alpha (SDF-1 alpha), expressed using the Sendai virus expression vector system, have been determined by x-ray crystallography at 2.0 Angstrom resolution. The crystal of form 1 is almost isomorphous with that used in the previous crystal structure analysis of the synthetic [N33A] mutant of SDF-1 alpha (Dealwis, C., et al, Proc. Natl. Acad. Sci. USA 1998;95, 6941-6946). However, the present structure analysis led to considerably better refinement statistics, revealing an error in the structural assignment of N-terminal residues in the previous report. Comparison of the solution structure, as previously determined by nuclear magnetic resonance (NMR) spectroscopy, and the present structure, with two monomers in the asymmetric unit, reveals several local conformational differences. Alanine scan mutagenesis studies for each residue in the so-called RFFESH motif revealed that only the first residue, Arg12, is effective in enhancing receptor binding (and successive activation). A new notion that steric restraint between Arg8 and Arg12 is favorable (if not vital) for retaining SDF activities appears to explain more consistently the structure-activity relationship data accumulated to date. Four guiding principles are presented that may be useful for designing potent therapeutic compounds interfering with HIV-1 infection through competition at the CXCR4 coreceptor.