硫氧还蛋白及其L97F变体酶切后片段自身重新结合为同源二聚体的稳定性和动力学研究  

Comparison of the Stability and Kinetics of the Self-Assembled Thioredoxin Fragments with It's L79F Mutant

作　　者：海尔汗[1] 武朝军[1] 罗素琴[2] 王建华[2] 

机构地区：[1]内蒙古工业大学化工学院 [2]内蒙古医学院药学系

出　　处：《内蒙古石油化工》2001年第4期5-9,34,共6页Inner Mongolia Petrochemical Industry

摘　　要：为了进一步研究蛋白质酶切后重新结合成同源二聚体时功能区域中残基的影响。本文选用硫氧还蛋白 (TRX)和硫氧还蛋白变体 (TRXL 97F)酶切后得到的两组片段 :N片段 (1 - 72 )和 C片段 (74- 1 0 8)作为研究对象。比较排在 79位的残基的改变对 N片段 (1 - 73 )和 C片段 (74- 1 0 8)作为研究对象。比较排在 79位的残基的改变对 N片段 (1 - 73 )和 C片段(74- 1 0 8)重新结合成同源二聚体的影响 ,得到以下结论 :1 .TRX中处于 β折叠状态的 β4 区域(P76 ,T77,L78,L79,L80 ,F81和 K82 ) 5中残基由链变为芳香环使 N片段和 C片段重新聚合成非共价同源二聚体的速率常数有所减小。 2 .这一变化对形成的同源二聚体的稳定性影响不大。The stability and kinetics of self-assembled complex may be effected by the size and charge of a residue in a α/β domain. We choose L79F mutant in which at position 79 leucine is substituted by Phenylalanine, the residue's size is bigger than in wild type TRX. After we compared the stability of the complex of the re-assembled N fragment and C fragment of wild type TRX with the complex of the re-assembled N fragment and C fragment of L79F mutant and their kinetics. We get the results:(1)The stability of re-assembled complex which N fragment (1-73) combines with C fragment from L79F is almost as the same as the complex from the wild type thioredxin.(2)The kinetics of the re-assembly complex of the L79F is different from that of wild type thioredoxin. The rate constant of the re-assembly of the L79F mutant's N fragment and C fragment is much lower than that of the wild type thioredoxin.

关 键 词：硫氧还蛋白 Β折叠 Α螺旋 动力学 离解常数 L97F 变体酶 自身重新结合 切后片段 稳定性 同源二聚体 

分 类 号：O629.73[理学—有机化学] Q51[理学—化学]