REACTIONS OF THE NAD RADICAL WITH HIGHER OXIDATION-STATES OF HORSERADISH-PEROXIDASE

被引:22
作者
KOBAYASHI, K [1 ]
HAYASHI, K [1 ]
SWALLOW, AJ [1 ]
机构
[1] CHRISTIE HOSP & HOLT RADIUM INST,PATTERSON INST CANC RES,MANCHESTER M20 9BX,LANCS,ENGLAND
关键词
D O I
10.1021/bi00460a017
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
The reactions of the NAD radical (NAD●) with ferric horseradish peroxidase and with compounds I and II were investigated by pulse radiolysis. NAD● reacted with the ferric enzyme and with compound I to form the ferrous enzyme and compound II with second-order rate constants of 8 × 108 and 1.5 × 108 M–1 s–1, respectively, at pH 7.0. In contrast, no reaction of NAD● with native compound II at pH 10.0 nor with diacetyldeutero-compound II at pH 5.0-8.0 could be detected. Other reducing species generated by pulse radiolysis, such as hydrated electron (eaq–), superoxide anion (O2–), and benzoate anion radical, could not reduce compound II of the enzyme to the ferric state, although the methylviologen radical reduced it. The results are discussed in relation to the mechanism of catalysis of the one-electron oxidation of substrates by peroxidase. © 1990, American Chemical Society. All rights reserved.
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页码:2080 / 2084
页数:5
相关论文
共 39 条
[1]   ENERGETICS OF THE ONE-ELECTRON STEPS IN THE NAD+-NADH REDOX COUPLE [J].
ANDERSON, RF .
BIOCHIMICA ET BIOPHYSICA ACTA, 1980, 590 (02) :277-281
[2]   STUDY OF PEROXIDASE MECHANISMS BY PULSE-RADIOLYSIS .3. RATE OF REACTION OF O2- AND HO2 RADICALS WITH HORSERADISH-PEROXIDASE COMPOUND I [J].
BIELSKI, BHJ ;
GEBICKI, JM .
BIOCHIMICA ET BIOPHYSICA ACTA, 1974, 364 (02) :233-235
[3]   HORSERADISH PEROXIDASE-CATALYZED OXIDATION OF IODIDE - OUTLINE OF MECHANISM [J].
BJORKSTEN, F .
BIOCHIMICA ET BIOPHYSICA ACTA, 1970, 212 (03) :396-+
[4]   CHARGE-TRANSFER BETWEEN TRYPTOPHAN AND TYROSINE IN PROTEINS [J].
BUTLER, J ;
LAND, EJ ;
PRUTZ, WA ;
SWALLOW, AJ .
BIOCHIMICA ET BIOPHYSICA ACTA, 1982, 705 (02) :150-162
[6]  
CHANCE B, 1954, MECHANISM ENZYME ACT, P389
[7]  
CORMIER MJ, 1968, J BIOL CHEM, V243, P4706
[8]   STUDIES ON HORSERADISH-PEROXIDASE .11. NATURE OF COMPOUNDS I AND II AS DETERMINED FROM KINETICS OF OXIDATION OF FERROCYANIDE [J].
COTTON, ML ;
DUNFORD, HB .
CANADIAN JOURNAL OF CHEMISTRY-REVUE CANADIENNE DE CHIMIE, 1973, 51 (04) :582-587
[9]   ELECTRON-TRANSFER FROM PYRIDINYL RADICALS, HYDRATED ELECTRONS, CO2.- AND O2.- TO BACTERIAL CYTOCHROME P450 [J].
DEBEY, P ;
LAND, EJ ;
SANTUS, R ;
SWALLOW, AJ .
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 1979, 86 (04) :953-960
[10]   BIPYRIDYLIUM QUATERNARY-SALTS AND RELATED COMPOUNDS .5. PULSE-RADIOLYSIS STUDIES OF REACTION OF PARAQUAT RADICAL WITH OXYGEN - IMPLICATIONS FOR MODE OF ACTION OF BIPYRIDYL HERBICIDES [J].
FARRINGTON, JA ;
EBERT, M ;
LAND, EJ ;
FLETCHER, K .
BIOCHIMICA ET BIOPHYSICA ACTA, 1973, 314 (03) :372-381