Tryptophan(Trp) residues in inulinase were modified by chemical reagent N-bromossuccinimide(NBS).The results of Spande′s method indicate that there were seventeen Trp residues in inulinase and five of them were locat...Tryptophan(Trp) residues in inulinase were modified by chemical reagent N-bromossuccinimide(NBS).The results of Spande′s method indicate that there were seventeen Trp residues in inulinase and five of them were located on the surface of the enzyme.Three of these Trp residues were none-essential residues which showed the fastest rate by Zhou′s plot.Two relative faster reacting residues were both essential for the activity of the enzyme.The other twelve were the slowest or none-reactive residues for the reaction.The study on fluorescence quenching of inulinase shows that KI could not quench all of the fluorescence from Trp residues in inulinase which indicate that there are two kinds of Trp residues in inulinase acrylamide(Acr),a polarized quencher without electronic charge could quench almost all of the fluorescence from Trp residues in inuoinase while there are still seventy percernt of the activity of the enzyme left.The collisional quenching constants(K_D) of inulinase at different concentrations of Acr were calculated in terms of Stern-Volmer equation.展开更多
Tryptophan residues in Hyaluronidase(HAase) were modified by N-bromosuccinimide(NBS). The results indicated that there were eleven tryptophan residues in HAase and one of them was exposed, which was proved to be essen...Tryptophan residues in Hyaluronidase(HAase) were modified by N-bromosuccinimide(NBS). The results indicated that there were eleven tryptophan residues in HAase and one of them was exposed, which was proved to be essential for the activity of the enzyme. The study on fluorescence quenching of HAase showed that KI could not quench all of the fluorescence from Trp residues in HAase . Acrylamide(Acr), a polarized quencher without electronic charge, could quench almost all of the fluorescence from Trp residues in HAase . The collisional quenching constants(K-D) of HAase at different concentrations of Acr were calculated in terms of Stern-Volmer equation. The results implied that some of Trp residues were buried in the interior of HAase, and the Trp residue on the surface of HAase was not located in the hydrophobic pocket.展开更多
文摘Tryptophan(Trp) residues in inulinase were modified by chemical reagent N-bromossuccinimide(NBS).The results of Spande′s method indicate that there were seventeen Trp residues in inulinase and five of them were located on the surface of the enzyme.Three of these Trp residues were none-essential residues which showed the fastest rate by Zhou′s plot.Two relative faster reacting residues were both essential for the activity of the enzyme.The other twelve were the slowest or none-reactive residues for the reaction.The study on fluorescence quenching of inulinase shows that KI could not quench all of the fluorescence from Trp residues in inulinase which indicate that there are two kinds of Trp residues in inulinase acrylamide(Acr),a polarized quencher without electronic charge could quench almost all of the fluorescence from Trp residues in inuoinase while there are still seventy percernt of the activity of the enzyme left.The collisional quenching constants(K_D) of inulinase at different concentrations of Acr were calculated in terms of Stern-Volmer equation.
文摘Tryptophan residues in Hyaluronidase(HAase) were modified by N-bromosuccinimide(NBS). The results indicated that there were eleven tryptophan residues in HAase and one of them was exposed, which was proved to be essential for the activity of the enzyme. The study on fluorescence quenching of HAase showed that KI could not quench all of the fluorescence from Trp residues in HAase . Acrylamide(Acr), a polarized quencher without electronic charge, could quench almost all of the fluorescence from Trp residues in HAase . The collisional quenching constants(K-D) of HAase at different concentrations of Acr were calculated in terms of Stern-Volmer equation. The results implied that some of Trp residues were buried in the interior of HAase, and the Trp residue on the surface of HAase was not located in the hydrophobic pocket.