Detailed circular dichroism(CD) and Fourier transform infrared(FTIR) studies have been carried out to monitor thermal unfolding of horseradish peroxidase isoenzyme C(HRP) inhibited by CN -(HRP CN). The results suggest...Detailed circular dichroism(CD) and Fourier transform infrared(FTIR) studies have been carried out to monitor thermal unfolding of horseradish peroxidase isoenzyme C(HRP) inhibited by CN -(HRP CN). The results suggest that HRP CN is quite different from native HRP with different spin states of Fe of heme and different coordinated states. Cyanide becomes the sixth ligand of Fe(Ⅲ) of heme and the hydrogen binding network is destroyed partly at the same time, which cause the drastic decrease of thermal stability of HRP. The FTIR and Soret CD spectra analysis demonstrate that during the heating process there is an intermediate state(I) which has both partly destroyed secondary and tertiary structures of native HRP, then it is the appearance of protein aggregation state(A) after fully unfolding. The unfolding pathway thus can be shown as follows: IIUA.展开更多
Aluminum pillared interlayered clay （Al-PILC） calcined at 773 K was the most appropriate support for immobilization of horseradish peroxidase （HRP） among several materials investigated.HRP could be immobilized on ...Aluminum pillared interlayered clay （Al-PILC） calcined at 773 K was the most appropriate support for immobilization of horseradish peroxidase （HRP） among several materials investigated.HRP could be immobilized on the Al-PILC via hydrogen bonding between functional groups of support and amino groups of the enzyme.The support and immobilized enzyme were characterized with N2-adsorption and desorption, XRD and FT-IR.An optimum condition for immobilization with enzyme immobilization efficiency of about 100% was obtained when the dose of support was greater than 0.45 mg per unit enzyme activity and reaction time exceeded 15 min.HRP immobilized on Al-PILC exhibited good catalytic performance.展开更多
文摘Detailed circular dichroism(CD) and Fourier transform infrared(FTIR) studies have been carried out to monitor thermal unfolding of horseradish peroxidase isoenzyme C(HRP) inhibited by CN -(HRP CN). The results suggest that HRP CN is quite different from native HRP with different spin states of Fe of heme and different coordinated states. Cyanide becomes the sixth ligand of Fe(Ⅲ) of heme and the hydrogen binding network is destroyed partly at the same time, which cause the drastic decrease of thermal stability of HRP. The FTIR and Soret CD spectra analysis demonstrate that during the heating process there is an intermediate state(I) which has both partly destroyed secondary and tertiary structures of native HRP, then it is the appearance of protein aggregation state(A) after fully unfolding. The unfolding pathway thus can be shown as follows: IIUA.
文摘Aluminum pillared interlayered clay （Al-PILC） calcined at 773 K was the most appropriate support for immobilization of horseradish peroxidase （HRP） among several materials investigated.HRP could be immobilized on the Al-PILC via hydrogen bonding between functional groups of support and amino groups of the enzyme.The support and immobilized enzyme were characterized with N2-adsorption and desorption, XRD and FT-IR.An optimum condition for immobilization with enzyme immobilization efficiency of about 100% was obtained when the dose of support was greater than 0.45 mg per unit enzyme activity and reaction time exceeded 15 min.HRP immobilized on Al-PILC exhibited good catalytic performance.
