Specific chemical cleavage in high yield at the amino peptide bonds of cysteine and cystine residues.
Specific chemical cleavage in high yield at the amino peptide bonds of cysteine and cystine residues.
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DOI：
10.1016/s0021-9258(19)43393-0
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发表时间：
1973-10
期刊：
影响因子：
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通讯作者：
Gary R. Jacobson;Martin H. Schaffer;George R. Stark;Thomas C. Vanaman
中科院分区：
文献类型：
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作者：
Gary R. Jacobson;Martin H. Schaffer;George R. Stark;Thomas C. Vanaman
提供了一种使用试剂2-硝基-5-硫氰基苯甲酸将蛋白质中的半胱氨酸和胱氨酸残基定量转化为S-氰基半胱氨酸残基的方案（Degani，Y.，Patchornik，A.（1971）J. Org. Chem. 36，2727）。在37° C下暴露于6 m氯化胍-0.1m硼酸钠（pH 9.0）12小时后，S-氰基半胱氨酸残基的氨基肽键断裂，同时形成2-亚氨基噻唑烷-4-羧基肽。该方法的应用到几种蛋白质表明，几乎完全裂解，可以获得，并有没有显着的副反应，由于暴露于碱性pH值。提出了一种机制的裂解反应，其中特定的氢氧根离子催化，其次是协调的肽键裂解和闭环，没有中间体形成的acyliminothiazolidine。
A protocol is presented for the quantitative conversion of cysteine and cystine residues in proteins to residues ofS-cyanocysteine, using the reagent 2-nitro-5-thiocyanobenzoic acid (Degani, Y.,andPatchornik, A. (1971)J. Org. Chem.36, 2727). Cleavage of the amino peptide bond of theS-cyanocysteine residue is obtained upon exposure to 6mguanidinium chloride-0.1msodium borate, pH 9.0, at 37° for 12 hours, with concomitant formation of 2-iminothiazolidine-4-carboxylyl peptides. Application of the method to several proteins indicates that virtually complete cleavage can be obtained and that there are no significant side reactions due to exposure to alkaline pH. A mechanism for the cleavage reaction is proposed in which specific hydroxide ion catalysis is followed by concerted peptide bond cleavage and ring closure, without the intermediate formation of an acyliminothiazolidine.