分子对接研究辛基酚与N-乙酰氨基葡萄糖苷酶的相互作用

摘要

有机污染物辛基酚(OP)在水体中广泛存在,危害水生生物健康．OP 暴露影响凡纳滨对虾 N-乙酰氨基葡萄糖苷酶(NAGase)活性,但其机制尚不明确．文章选取对辛基酚(p-OP)、邻辛基酚(o-OP)和间辛基酚(m-OP)3种异构体,分析它们与 NAGase 的相互作用机制．首先利用 Autodock-tools 和 OpenBabel 软件对NAGase和 OP的构象进行处理,再用 Autodock vina 软件进行分子对接,用 PyMol 和 Discovery Studio 分析两者对接的结合能量、结合方式和相互作用力．结果显示,辛基酚3种异构体和 NAGase的相互作用机制有所差异．NAGase和辛基酚的3种异构体结合的能量分别为－20．9,－21．4,－24．7 kJ/mol；p-OP 和 NAGase 通过2个氢键和2个疏水键结合,对接位点在 NAGase B链的 Pro132、Phe137、Ala140和 A 链的 Val592；o-OP和NAGase通过1个氢键和1个疏水键结合,对接位点在NAGase B链的Phe134和A链的Leu595；m-OP和NAGase通过1个氢键和3个疏水键结合,对接位点在 NAGase B链的 Val592和 A 链的 Phe134、Gln127和Phe553．以上研究结果有助于理清 OP影响 NAGase的分子机制．%Octyl-phenol (OP)is widely spread in the aquatic environment and shows adverse health im-pact to aquatic organisms.Exposure to OP disturbed the activity of N-acetylglucosaminidase (NA-Gase)in Litopenaeus vannamei.However,its inner mechanism is still unclear.In this study,three iso-mers of OP were selected to study the interactions between octyl-phenol(OP)isomers and NAGase. The conformations of OP and NAGase are processed by Autodock-tools 1 .5 .6 and OpenBabel,then the molecular docking of OP and NAGase is simulated by Autodock vina,finally the binding energy,bind-ing sites and the interaction forces of OP and NAGase are analyzed by PyMol and Discovery Studio 4.1.The results show that the interaction mechanisms of three OP isomers and NAGase make some differ-ences.The energies of para-OP (p-OP),ortho-OP (o-OP),meta-OP (m-OP)binding with NAGase are-20.9,-21.4 and -24.7 kJ/mol,respectively.p-OP interacts with NAGase through one hydrophobic bond and two hydrophobic bonds,the binding sites are Val592 in A chain and Pro132,Phe137,Ala140 in B chain of NAGase.o-OP interacts with NAGase through one hydrogen bond and one hydrophobic bond,the binding sites are Leu595 in A chain and Phe134 in B chain.m-OP interacts with NAGase through one hydrogen bond and three hydrophobic bonds,and the binding sites are Phe134,Gln127, Phe553 in A chain and Val592 in B chain of NAGase.The results will help the understanding of the in-teractive mechanism between OP and NAGase.