Department of Biology, Faculty of Science, Razi University, Kermanshah, Iran.
Int J Biol Macromol. 2012 May 1;50(4):910-7. doi: 10.1016/j.ijbiomac.2012.02.005. Epub 2012 Feb 16.
This study reports the interaction between furosemide and human carbonic anhydrase II (hCA II) using fluorescence, UV-vis and circular dichroism (CD) spectroscopy. Fluorescence data indicated that furosemide quenches the intrinsic fluorescence of the enzyme via a static mechanism and hydrogen bonding and van der Walls interactions play the major role in the drug binding. The binding average distance between furosemide and hCA II was estimated on the basis of the theory of Förster energy transfer. Decrease of protein surface hydrophobicity was also documented upon furosemide binding. Chemical modification of hCA II using N-bromosuccinimide indicated decrease of the number of accessible tryptophans in the presence of furosemide. CD results suggested the occurance of some alterations in α-helical content as well as tertiary structure of hCA II upon drug binding.
本研究采用荧光、紫外-可见和圆二色（CD）光谱法报告了速尿与人类碳酸酐酶 II（hCA II）之间的相互作用。荧光数据表明，速尿通过静态机制猝灭酶的固有荧光，氢键和范德华相互作用在药物结合中起主要作用。基于福斯特能量转移理论，估算了速尿与 hCA II 之间的结合平均距离。速尿结合还记录了蛋白质表面疏水性的降低。使用 N-溴代丁二酰亚胺对 hCA II 进行化学修饰表明，在存在速尿的情况下，可及色氨酸的数量减少。CD 结果表明，药物结合后 hCA II 的α-螺旋含量和三级结构发生了一些变化。
