發(fā)布時間：2018-03-28 00:11

  本文選題：人血清白蛋白　切入點：氟羅沙星　出處：《光譜學與光譜分析》2017年01期

【摘要】：氟羅沙星(FLRX)是一種含氟喹諾酮類抗菌素,有關(guān)它對人血清白蛋白(HSA)的影響及作用機理,特別是對HSA二級結(jié)構(gòu)的影響及內(nèi)濾光(影響熒光數(shù)據(jù)的準確性)校正的研究報道較少。采用多光譜法和分子模擬技術(shù)探究了FLRX與HSA的相互作用。熒光光譜結(jié)果表明,FLRX對HSA的猝滅是由于形成結(jié)合常數(shù)在105 L·mol~(-1)水平上的1∶1FLRX-HSA基態(tài)復合物引起的靜態(tài)猝滅作用。由Van’t Hoff方程確定的FLRX與HSA結(jié)合過程中的ΔH=-107.99kJ·mol~(-1)和ΔS=-240.99J·mol~(-1)·K~(-1),表明FLRX與HSA之間的主要作用力是氫鍵和范德華力。同步熒光光譜、紅外光譜和三維熒光光譜結(jié)果表明,靜態(tài)猝滅過程所產(chǎn)生的中間復合物使HSA的構(gòu)象發(fā)生改變。通過對HSA與FLRX作用前后紅外光譜酰胺Ⅰ帶進行傅里葉去卷積和分峰擬合,獲得代表HSA二級結(jié)構(gòu)的不同子峰,對各子峰進行二級結(jié)構(gòu)歸屬,根據(jù)各子峰的積分面積計算出各二級結(jié)構(gòu)的相對百分含量。結(jié)果表明:FLRX與HSA結(jié)合后,α-螺旋從51.5%減小到33.2%,β-折疊從30.3%減小到20.7%,β-轉(zhuǎn)角從15.6%增加到33.6%。取代實驗顯示FLRX與HSA的結(jié)合位點在HSA的siteⅠ(亞域ⅡA)。分子對接實驗結(jié)果表明,FLRX可以通過氫鍵、疏水作用和范德華力等多種作用力很好的結(jié)合在亞域ⅡA的疏水腔中。實驗獲得的可信數(shù)據(jù)將有助于闡明FLRX與HSA的作用機制,也有助于理解FLRX在儲運過程中對蛋白質(zhì)功能的影響。
[Abstract]:Fleroxacin (FLRX) is a fluoroquinolone antibiotic. The effect of FLRX on human serum albumin (HSA) and its mechanism of action are discussed. Especially, the influence of secondary structure of HSA and the correction of internal filter (affecting the accuracy of fluorescence data) were seldom reported. The interaction between FLRX and HSA was studied by means of multispectral method and molecular simulation. The quenching of HSA is caused by the formation of 1:1FLRX-HSA ground state complexes at the binding constant of 105L mol / L. The 螖 H=-107.99kJ molanine (-1) and 螖 Sn-240.99J molan-1 (K-1) determined by the Van't Hoff equation in the binding process between FLRX and HSA indicate that the main mechanism between FLRX and HSA is the formation of the FLRX / HSA complex at the level of 105L / mol ~ (-1), indicating that the interaction between FLRX and HSA is mainly due to the interaction between FLRX and HSA. Force is hydrogen bond and van der Waals force. Synchronous fluorescence spectrum, The results of IR and 3D fluorescence spectra showed that the conformation of HSA was changed by the intermediate complex produced by static quenching process. The Fourier deconvolution and peak fitting of the amide I band of IR spectrum before and after the interaction of HSA with FLRX were carried out. Different sub-peaks representing the secondary structure of HSA were obtained, and the secondary structure of each sub-peak was assigned. According to the integral area of each sub-peak, the relative percentage content of each secondary structure is calculated. The results show that the 偽 -helix decreases from 51.5% to 33.2%, the 尾 -fold decreases from 30.3% to 20.7 and the 尾 -rotation angle increases from 15.6% to 33.6um after combining with HSA. The molecular docking results showed that the molecular docking site of HSA could be obtained by hydrogen bonding. The hydrophobic interaction and van der Waals force are well combined in the hydrophobic cavity of subdomain 鈪，

本文編號：1673878