The amino acid sequence of dihydrofolate reductase from the mouse lymphoma L1210.
The amino acid sequence of dihydrofolate reductase from the mouse lymphoma L1210.
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小鼠淋巴瘤 L1210 的二氢叶酸还原酶的氨基酸序列。
DOI：
10.1016/s0021-9258(17)37942-5
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发表时间：
1979
期刊：
影响因子：
--
通讯作者：
A. W. Phillips
中科院分区：
文献类型：
--
作者：
D. Stone;S. Paterson;J. H. Raper;A. W. Phillips
描述了从小鼠淋巴瘤L1210细胞中测定二氢叶酸还原酶（EC 1.5.1.3）的氨基酸序列。用溴化氰切割蛋白质，产生6个片段CB 1（残基1至14）、CB 2（残基15至52）、CB 3（残基53至111）、CB 4（残基115至125）、CB 5（残基126至139）和CB 6（残基140至186）。其中一个片段，CB 2，含有一个内部高丝氨酸来自甲硫氨酸，这是不裂解溴化氰。溴化氰片段的氨基酸序列和顺序通过对来自胰蛋白酶、嗜热链球菌和金黄色葡萄球菌蛋白酶digestion的片段和小肽的自动和手动序列分析的组合来确定。完整序列在分子量为21，458的单一多肽链中包含186个残基。L1210二氢叶酸还原酶的序列与来自屎链球菌、大肠杆菌RT500和干酪乳杆菌的酶的序列的比较表明，所有酶显示出一定的同源性，这在形成底物结合裂缝的区域中是最强的。
The determination of the amino acid sequence of the dihydrofolate reductase (EC 1.5.1.3) from cells of the mouse lymphoma L1210 is described. The protein was cleaved by cyanogen bromide to produce the six fragments CB1 (residues 1 to 14), CB2 (residues 15 to 52), CB3 (residues 53 to 111), CB4 (residues 115 to 125), CB5 (residues 126 to 139), and CB6 (residues 140 to 186). One of the fragments, CB2, contained an internal homoserine derived from a methionine which was not cleaved by cyanogen bromide. The amino acid sequences and order of the cyanogen bromide fragments were determined by a combination of automatic and manual sequence analyses of the fragments and small peptides from tryptic, thermolytic, and Staphylococcus aureus protease digestions. The complete sequence comprises 186 residues in a single polypeptide chain of molecular weight 21,458. Comparison of the sequence of the L1210 dihydrofolate reductase with the sequences of the enzymes from Streptococcus faecium, escherichia coli RT500, and Lactobacillus casei indicates that all enzymes show some homology, which is strongest in the regions forming the substrate binding cleft.