Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT, 06030, USA.
Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, 02115, USA.
Biomol NMR Assign. 2021 Oct;15(2):281-285. doi: 10.1007/s12104-021-10018-7. Epub 2021 Mar 24.
The E. coli γ clamp loader is a pentameric complex of δ, δ' and three γ subunits that opens and loads β-clamp proteins onto DNA in an ATP-dependent process essential for efficient DNA replication. ATP binding to the γ subunits promotes conformational changes that enable the clamp loader to bind and open the ring-shaped β-clamp homodimer. Here we report the nearly complete backbone and side-chain H, C and N NMR resonance assignments of the 242-residue truncated γ subunit of the clamp loader complex, which includes the N-terminal mini (domain I) and lid (domain II) domains. This construct represents the nucleotide binding module in the clamp loader complex and provides a model system for studies of conformational rearrangements of the clamp loader induced by nucleotide binding.
大肠杆菌γ 夹钳加载器是一个由δ、δ'和三个γ 亚基组成的五聚体复合物，通过一个 ATP 依赖的过程打开并将β-夹钳蛋白加载到 DNA 上，这个过程对于有效的 DNA 复制至关重要。ATP 与γ 亚基结合促进构象变化，使夹钳加载器能够结合并打开环形β-夹钳同源二聚体。在这里，我们报道了夹钳加载器复合物中 242 个残基截断的γ 亚基的近完整的 backbone 和侧链 H、C 和 N NMR 共振分配，其中包括 N 端的 mini（结构域 I）和 lid（结构域 II）结构域。这个构建体代表了夹钳加载器复合物中的核苷酸结合模块，并为研究核苷酸结合诱导的夹钳加载器构象重排提供了一个模型系统。
