Abstract:The guanidinium chloride denaturation/renaturation of the holo and apo soybean hull peroxidase(SHP,EC 1.11.1.7) was studied by fluorescence spectroscopy.A distinct equilibrium intermediate of the apoprotein could be detected at low concentrations of guanidinium chloride.Renaturation of the apo SHP was reversible.The denaturation of the holo SHP was more complex.In addition,the stability of the enzyme following treatment with periodate was studied.This treatment resulted in a loss of specific activity which was shown not to be correlated with the removal of sugars.The thermal stability was found decreased by this chemical deglycosylation.Finally,the effects of some protein modification reagents on the activity of SHP were studied.The enzyme was not affected by DTNB,IAA,HNBB and NAI modification,suggesting amino groups,thiol groups,tyrosyl and tryptophanyl residues were non essential to enzyme activity.The enzyme activity was remarkably decreased after DEPC,PGH,WRK and EDC modification.The results indicated histidyl residues,arginyl residues and carboxyl groups seemed to be essential to the catalytic acticvity of SHP.
刘稳,方靖,高培基. 豆壳过氧化物酶的盐酸胍变性与化学修饰研究[J]. 中国生物化学与分子生物学报, 1999, 15(05): 802-807.
LIU Wen,FANG Jing,GAO Peiji. Chemical Modification and Guanidinium Chloride Denaturation of Soybean Hull Peroxidase. Chinese Journal of Biochemistry and Molecular Biol, 1999, 15(05): 802-807.