Model Study on Asymmetry-Inducing and Recognizing Ability of Peptide Chains

肽链不对称诱导与识别能力的模型研究

基本信息

批准号：
09450344
负责人：
OHKATSU Yasukatsu
金额：
$ 9.02万
依托单位：
Kogakuin University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1999
项目状态：
已结题

项目摘要

The function of an enzyme consisting of proteins is explained by 'lock and key' theory, which is convenient to explain specificities of the enzyme, but it cannot explain fast enzymatic reaction. The applicant assumed that the conformation of peptide chains around the active site of an enzyme provides the specificity of enzyme, even if the space around active site is wide or is not controlled by peptide chains, and has gotten a few evidences that this assumption is correct on basis of model reactions. In first year, porphyrin complexes having peptide chains on the meso positions were synthesized as model of cytochrome P-450. These are completely different from models proposed so far, at the point that it has a wide space around active site, but nevertheless attained high asymmetric induction and high reaction rates at the same time, especially depending on the content of α-helix.. In second year, the applicant found that several glycoproteins are models of α-chymotrypsin and also found that they recognize R,S-configuration of amino acids by a-helix of the peptide conformation. In this year, a kind of glycoproteins were found to be esterase models in non-aqueous medium, but they do not seem to induce asymmetry of esterification products on basis of the β-sheet conformation.As mentioned above, it is proposed that the specificity of an enzyme is derived from α-helix of peptide chains, even if the space around the active site is not narrow as taught by 'key and lock' theory.

由蛋白质组成的酶的功能由“锁定和关键”理论解释，这很方便地解释酶的规范，但无法解释快速酶促反应。所需的效果是，即使活性位点周围的空间宽或不受肽链的控制，并且有一些证据表明，这种假设是正确的，即使酶的活性位点周围的肽链的组成也提供了酶的特异性。在第一年，将具有辣椒链的卟啉配合物合成为细胞色素P-450的模型。这些与到目前为止提出的模型完全不同，以至于它在活跃的地点周围具有很大的空间，但是同时又附上了高的不对称诱导和高反应速率，尤其是取决于α-螺旋的含量。在第二年，适用的是，几个糖蛋白发现，几个糖蛋白是α-糖蛋白的模型，并且发现它们的模型，它们识别出Amino ratix a aminix a aminix a amanfient a amfiration ramfiix a am andirix a am andirix a am andix a am andix and-peltiration a am andinfient rafiix and-pertiix and-pertiix。构象。 In this year, a kind of glycoproteins were found to be esterase models in non-aqueous medium, but they do not seem to induce asymmetry of esterification products on basis of the β-sheet conformation.As mentioned above, it is proposed that the specificity of an enzyme is derived from α-helix of peptide chains, even if the space around the active site is not narrow as taught by 'key and lock' theory.