Islam A, Persson B, Zaidi Z H, Jörnvall H
Department of Chemistry I, Karolinska Institutet, Stockholm, Sweden.
J Protein Chem. 1990 Oct;9(5):533-41. doi: 10.1007/BF01025006.
The hemoglobin of the sea snake Microcephalophis gracilis was purified and the primary structure of the alpha and beta chains determined. This is the first sea snake hemoglobin structure characterized, and apparently also the first complete structure of any snake hemoglobin (an alpha chain of a viper was known), allowing judgments of reptilian variants. Variations between the sea snake form and other reptilian forms are large (52-65 differences for the alpha chains), of similar order as those between the sea snake and avian (56-65 differences) or human (58 differences) forms. Functionally, 19 residues at alpha/beta contact areas and 7 at heme contacts are exchanged in relation to the human alpha and beta chains. Four positions of the sea snake hemoglobin contain residues thus far unique to this form. However, all replacements appear compatible with conserved overall functional properties.
对细小头海蛇的血红蛋白进行了纯化，并确定了其α链和β链的一级结构。这是首个被表征的海蛇血红蛋白结构，显然也是任何蛇类血红蛋白的首个完整结构（已知一种蝰蛇的α链），从而能够对爬行类动物的变体进行判断。海蛇形式与其他爬行类形式之间的差异很大（α链有52 - 65个差异），与海蛇和鸟类形式（56 - 65个差异）或人类形式（58个差异）之间的差异处于相似水平。在功能上，相对于人类α链和β链，α/β接触区域有19个残基以及血红素接触区域有7个残基发生了交换。海蛇血红蛋白的四个位置含有迄今为止该形式所特有的残基。然而，所有这些替换似乎都与保守的整体功能特性相符。
