High-resolution structure of human cytoglobin: identification of extra N- and C-termini and a new dimerization mode
High-resolution structure of human cytoglobin: identification of extra N- and C-termini and a new dimerization mode
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DOI：
10.1107/s0907444906013813
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发表时间：
2006-06-01
影响因子：
2.2
通讯作者：
Shiro, Yoshitsugu
中科院分区：
文献类型：
--
作者：
Makino, Masatomo;Sugimoto, Hiroshi;Shiro, Yoshitsugu
细胞珠蛋白（Cytoglobin，Cgb）是近年来发现的脊椎动物血红蛋白家族成员。以1.68（A）的圆分辨率确定了野生型人Cgb（空间群C2）的新晶体形式的结构。结果表明，在A螺旋之前的N-末端残基中存在额外的螺旋（4-20），并且在C-末端区域中存在有序的环结构（168-188），而这些延伸的肽由于先前报道的结构中的无序而不可见，使用P3（2）21晶体，在2.4（A）的分辨率下在圆上。两种晶体结构的详细比较显示，由于不同的二聚体排列，血红素环境中的残基（即Arg 84）的构象存在差异。
Cytoglobin ( Cgb) is a recently discovered member of the vertebrate haem-containing globin family. The structure of a new crystal form of wild-type human Cgb ( space group C2) was determined at a resolution of 1.68 (A) over circle. The results show the presence of an additional helix in the N-terminal residues ( 4-20) prior to the A helix and an ordered loop structure in the C-terminal region ( 168-188), while these extended peptides were invisible owing to disorder in the previously reported structures using a P3(2)21 crystal at a resolution of 2.4 (A) over circle. A detailed comparison of the two crystal structures shows differences in the conformation of the residues ( i.e. Arg84) in the haem environment owing to a different dimeric arrangement.