A cholesterol oxidase(COD)was hybridized with Ca^(2+),Zn^(2+),Al^(3+),Fe^(2+) and Mn^(2+).After precipitation with PO_(4)^(3-) at 4℃ for 72 h,the resulting pellets were freeze-dried.In scanning electron microscopy as...A cholesterol oxidase(COD)was hybridized with Ca^(2+),Zn^(2+),Al^(3+),Fe^(2+) and Mn^(2+).After precipitation with PO_(4)^(3-) at 4℃ for 72 h,the resulting pellets were freeze-dried.In scanning electron microscopy assays,the metal-COD complexes revealed flower-like or granular structures after hybridization.Fourier transform infrared spectroscopy assay revealed the characteristic peaks of both the enzyme and metal materials.X-ray diffraction analysis indicated that COD was encapsulated in CaHPO_(4)·2H_(2)O-,Zn_(3)(PO_(4))_(2)·4H_(2)O-,AlPO_(4-),FeP_(4-) and Mn_(3)(PO_(4))_(2)·3H_(2)O-based nanostructures,respectively.Differential scanning calorimetry assay indicated significant increases in thermo-denaturation temperatures from 60.5℃ to 167.02℃,167.02℃,137.70℃,172.85℃ and 160.99℃,respectively.Using steroid derivatives as substrates,this enzyme could convert cholesterol,pregnenolone,dehydroepiandrosterone,ergosterol,b-sitosterol and stigmasterol to related single products.Hybridization in metal-based nanostructures could significantly enhance the initial conversion ratio and reaction stability of the enzyme.In addition,substrate selectivity could be affected by various metal materials.Briefly,using Ca^(2+),Zn^(2+),Al^(3+),Fe^(2+) and Mn^(2+) as hybrid raw materials could help to encapsulate COD in related metal-enzyme nanostructures,and could help to promote the stability and tolerant properties of the enzyme,while also enhancing its catalytic characteristics.展开更多
基金supported by the National Key Research and Development Program of China(Grant No.2018YFA0900304-300)the Natural Science Foundation of Jiangsu Province(Grant Nos.BK20160053 and BE2018055)the Priority Academic Program Development of Jiangsu Higher Education Institutions,111 Project(Grant No.111-2-06).
文摘A cholesterol oxidase(COD)was hybridized with Ca^(2+),Zn^(2+),Al^(3+),Fe^(2+) and Mn^(2+).After precipitation with PO_(4)^(3-) at 4℃ for 72 h,the resulting pellets were freeze-dried.In scanning electron microscopy assays,the metal-COD complexes revealed flower-like or granular structures after hybridization.Fourier transform infrared spectroscopy assay revealed the characteristic peaks of both the enzyme and metal materials.X-ray diffraction analysis indicated that COD was encapsulated in CaHPO_(4)·2H_(2)O-,Zn_(3)(PO_(4))_(2)·4H_(2)O-,AlPO_(4-),FeP_(4-) and Mn_(3)(PO_(4))_(2)·3H_(2)O-based nanostructures,respectively.Differential scanning calorimetry assay indicated significant increases in thermo-denaturation temperatures from 60.5℃ to 167.02℃,167.02℃,137.70℃,172.85℃ and 160.99℃,respectively.Using steroid derivatives as substrates,this enzyme could convert cholesterol,pregnenolone,dehydroepiandrosterone,ergosterol,b-sitosterol and stigmasterol to related single products.Hybridization in metal-based nanostructures could significantly enhance the initial conversion ratio and reaction stability of the enzyme.In addition,substrate selectivity could be affected by various metal materials.Briefly,using Ca^(2+),Zn^(2+),Al^(3+),Fe^(2+) and Mn^(2+) as hybrid raw materials could help to encapsulate COD in related metal-enzyme nanostructures,and could help to promote the stability and tolerant properties of the enzyme,while also enhancing its catalytic characteristics.
