A possible hydrolysis mechanism of β—naphthyl acetate catalyzed by antibodies

在线阅读 下载PDF 导出详情
摘要 Themechanismofesterhydrolysishasbeenextensivelystudied;however,theprecisefunctionofactive-siteresiduesinpromotingcatalysisisunclear.WedescribeherethestructuralmodelsforthecomplexofacatalyticantibodyFvfragmentwithaphosphonatetransition-stateanalogue,constructedbyusinggenecloning,sequencingandmolecularmodeling,mainlybasedonaknownX-raystructureofacatalyticantibody.HydrophobicandelectrostaticanalysesoftheFv/analogandFv/substrateinteractionsuggestthehydrolysismechanism:TyrL91andTyrH97playimportantrolestostabilizetheβ-naphthylgroupofhaptenthroughπ-stack;HisH35donatesapairoffreeelectronsattheatomNE2toanactivewaterandletittobeapartialhydroxide,whichattacksthecarbonatomofthecarbonylgroupofthesubstrate.BothHisH35andArgL96canformhydrogenbondsandstabilizetheanionictetrahedralintermediateformedduringturnover.Thismechanismemphasizesthatanactivewaterbridgemaybeformedduringhydrolysisprocess.
机构地区 不详
出处 《细胞研究:英文版》 1998年3期
出版日期 1998年03月13日(中国期刊网平台首次上网日期,不代表论文的发表时间)
  • 相关文献