Noncovalent interactions between ligands and targeting proteins are essential for understanding molecular mechanisms of proteins.In this work,we investigated the interaction of Cytochrome c(Cyt c)with maltoligosacchar...Noncovalent interactions between ligands and targeting proteins are essential for understanding molecular mechanisms of proteins.In this work,we investigated the interaction of Cytochrome c(Cyt c)with maltoligosaccharides,namely maltose(Mal Ⅱ),maltotriose(Mal Ⅲ),maltotetraose(Mal Ⅳ),maltopentaose(Mal Ⅴ),maltohexaose(Mal Ⅵ)and maltoheptaose(Mal Ⅶ).Using electrospray ionization mass spetrometry(ESI-MS)assay,the 1:1 and 1:2 complexes formed by Cyt c with maltoligosaccharide ligand were observed.The corresponding association constants were calculated according to the deconvoluted spectra.The order of the relative binding affinities of the selected oligosaccharides with Cyt c were as MalⅢ>MalⅣ>MalⅡ>MalⅤ>MalⅥ>MalⅦ.The results indicated that the stability of noncovalent protein complexes was intimately correlated to the molecular structure of bound ligand.The relevant functional groups that could form H-bonds,electrostatic or hydrophobic forces with protein’s amino residues played an important role for the stability of protein complexes.In addition,the steric structure of ligand was also critical for an appropriate interaction with the binding pocket of proteins.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.21675176)the Natural Science Foundation of Hubei Province(Grant No.2014CFA025)the Preferred Research Foundation for the Returned Overseas Scholars from Ministry of Human Resources and Social Security of the People’s Republic of China(Grant No.BZY14036)for financial supports.
文摘Noncovalent interactions between ligands and targeting proteins are essential for understanding molecular mechanisms of proteins.In this work,we investigated the interaction of Cytochrome c(Cyt c)with maltoligosaccharides,namely maltose(Mal Ⅱ),maltotriose(Mal Ⅲ),maltotetraose(Mal Ⅳ),maltopentaose(Mal Ⅴ),maltohexaose(Mal Ⅵ)and maltoheptaose(Mal Ⅶ).Using electrospray ionization mass spetrometry(ESI-MS)assay,the 1:1 and 1:2 complexes formed by Cyt c with maltoligosaccharide ligand were observed.The corresponding association constants were calculated according to the deconvoluted spectra.The order of the relative binding affinities of the selected oligosaccharides with Cyt c were as MalⅢ>MalⅣ>MalⅡ>MalⅤ>MalⅥ>MalⅦ.The results indicated that the stability of noncovalent protein complexes was intimately correlated to the molecular structure of bound ligand.The relevant functional groups that could form H-bonds,electrostatic or hydrophobic forces with protein’s amino residues played an important role for the stability of protein complexes.In addition,the steric structure of ligand was also critical for an appropriate interaction with the binding pocket of proteins.
