Chung Kim C Chan, Cao Li, Dias Alistair V, Pickering Ingrid J, George Graham N, Zamble Deborah B
Department of Chemistry, University of Toronto, Toronto, Ontario, Canada M5S 3H6.
J Am Chem Soc. 2008 Oct 29;130(43):14056-7. doi: 10.1021/ja8055003. Epub 2008 Oct 4.
The high-affinity nickel-binding site of the Escherichia coli [NiFe]-hydrogenase accessory protein HypB was localized to residues at the immediate N-terminus of the protein. Modification of a metal-binding fusion protein, site-directed mutagenesis experiments, and DFT calculations were used to identify the N-terminal amine as a ligand as well as the three cysteine residues in the CXXCGCXXX motif. This sequence can be removed from the protein and both a synthesized peptide and a protein fusion bind nickel with a similar affinity and the same structure as the parent metalloprotein, indicating the self-sufficiency of this high-affinity nickel-binding sequence.
大肠杆菌[NiFe]氢化酶辅助蛋白HypB的高亲和力镍结合位点定位于该蛋白紧邻N端的残基处。通过修饰金属结合融合蛋白、定点诱变实验和密度泛函理论计算，确定N端胺基以及CXXCGCXXX基序中的三个半胱氨酸残基为配体。该序列可从蛋白中去除，合成肽和蛋白融合体均能以与亲本金属蛋白相似的亲和力和相同的结构结合镍，表明该高亲和力镍结合序列具有自足性。
