Department of Biochemistry, Faculty of Life Science, Aligarh Muslim University, Aligarh 202002, India.
Department of Biochemistry, Faculty of Life Science, Aligarh Muslim University, Aligarh 202002, India.
Int J Biol Macromol. 2014 Mar;64:36-44. doi: 10.1016/j.ijbiomac.2013.11.010. Epub 2013 Nov 28.
Physiological conditions corresponding to oxidative stress deplete the level of enzyme glyoxalase, facilitating a hike in the serum concentration of glyoxal. Simulating an elevated in vivo level of glyoxal, we tested (50%, v/v) concentration of glyoxal to interact with HEWL. Initially, docking study revealed that glyoxal binds in the hydrophobic core of the enzyme. The interaction between the dialdehyde (glyoxal) and the enzyme (HEWL) followed a three step transition involving pre-molten and molten globule states formed on days 7 and 15 of incubation respectively, which were characterised by an increase in the ANS fluorescence intensity compared to the native state. These molten globule states upon further incubation on day 20 resulted in the formation of aggregates which were characterised by an increase in ThT fluorescence intensity, red shift in Congo red absorbance, negative ellipticity peak at 217 nm in the far-UV CD and the loss of signals at 284, 290 and 294 nm in the near-UV CD spectra. Finally, TEM confirmed the authenticity of lysozyme fibril formation by displaying rod like fibrillar structure.
生理条件对应氧化应激耗尽了酶甘油醛酶的水平,促进了血清甘油醛浓度的升高。模拟体内甘油醛水平升高,我们测试了(50%,v/v)浓度的甘油醛与 HEWL 相互作用。最初,对接研究表明甘油醛结合在酶的疏水核心中。醛(甘油醛)与酶(HEWL)之间的相互作用经历了三个步骤的转变,涉及预熔化和熔化球蛋白状态,分别在孵育的第 7 天和第 15 天形成,与天然状态相比,ANS 荧光强度增加。这些熔化球蛋白状态在孵育第 20 天进一步形成聚集体,其特征是 ThT 荧光强度增加,刚果红吸收红移,远紫外 CD 中 217nm 处负椭圆度峰增加,以及近紫外 CD 谱中 284nm、290nm 和 294nm 处信号的损失。最后,TEM 通过显示棒状纤维状结构证实了溶菌酶纤维形成的真实性。