Jones B N, Rothgeb T M, England R D, Gurd F R
Biochim Biophys Acta. 1979 Apr 25;577(2):464-74. doi: 10.1016/0005-2795(79)90050-3.
The complete amino acid sequence of the major component myoglobin from Pacific sei whale, Balaenoptera borealis, was determined by specific cleavage of the protein to obtain large peptides which are readily degraded by the automatic sequencer. The acetimidated apomyoglobin was selectively cleaved at its two methionyl residues with cyanogen bromide and at its three arginyl residues by trypsin. From the sequence analysis of four of these peptides and the apomyoglobin, over 75% of the covalent structure of the protein was obtained. The remainder of the primary structure was determined by the sequence analysis of peptides that resulted from further digestion of the amino-terminal and central cyanogen bromide fragments. The amino-terminal fragment was specifically cleaved at its two tryptophanyl residues with N-chlorosuccinimide and the central cyanogen bromide fragment was cleaved at its glutamyl residues with staphylococcal protease and at its single tyrosyl residue with N-bromosuccinimide. The primary structure of this myoglobin proved identical with that from the gray whale but differs from that of the finback whale at four positions, from that of the minke whale at three positions and from the myoglobin of the humpback whale at one position. The above sequence identities and differences reflect the close taxonomic relationship of these five species of Cetacea.
通过对太平洋鳁鲸（Balaenoptera borealis）主要成分肌红蛋白进行特异性切割，获得易于被自动测序仪降解的大肽段，从而确定了其完整的氨基酸序列。对乙酰亚胺化的脱辅基肌红蛋白，用溴化氰选择性切割其两个甲硫氨酰残基，并用胰蛋白酶切割其三个精氨酰残基。通过对其中四个肽段和脱辅基肌红蛋白的序列分析，获得了该蛋白质超过75%的共价结构。其余的一级结构通过对氨基末端和中央溴化氰片段进一步消化产生的肽段进行序列分析来确定。氨基末端片段用N-氯代琥珀酰亚胺在其两个色氨酰残基处特异性切割，中央溴化氰片段用葡萄球菌蛋白酶在其谷氨酰残基处切割，并用N-溴代琥珀酰亚胺在其单个酪氨酰残基处切割。这种肌红蛋白的一级结构被证明与灰鲸的相同，但在四个位置上与长须鲸的不同，在三个位置上与小须鲸的不同，在一个位置上与座头鲸的肌红蛋白不同。上述序列的相同和差异反映了这五种鲸目动物在分类学上的密切关系。
