NADH:Fe(III)-chelate reductase of maize roots is an active cytochrome b(5) reductase

被引：21

作者：

Sparla, F ^{[1
]}

Bagnaresi, P ^{[1
]}

Scagliarini, S ^{[1
]}

Trost, P ^{[1
]}

机构：

[1] UNIV BOLOGNA,DIPARTIMENTO BIOL EVOLUZ SPERIMENTALE,I-40126 BOLOGNA,ITALY

来源：

FEBS LETTERS | 1997年 / 414卷 / 03期

关键词：

iron reduction; NADH:Fe(III)-chelate reductase; Fe(III)-citrate; cytochrome b(5) reductase; Zea mays;

D O I：

10.1016/S0014-5793(97)01073-9

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：

Microsomal NADH:Fe(III)-chelate reductase (NFR) of maize roots has been purified as a monomeric flavoprotein of 32 kDa with non-covalently bound FAD. In the presence of NADH, NFR efficiently reduced the physiological iron-chelate Fe(III)-citrate (K-cat/K-m(Fe(III-citrate)) = 6.0 X 10(6) M-1 s(-1)) with a sequential reaction mechanism, Purified NFR was totally inhibited by the sulfhydryl reagent PHMB at 10(-9) M, and it could use cyt b(5) as alternative electron acceptor with a maximal reduction rate as high as with Fe(III)-citrate. We conclude that in maize roots the reduction of Fe(III)-citrate is chiefly performed by a cytochrome b(5) reductase, mostly associated with intracellular membranes and in part with the plasma membrane. (C) 1997 Federation of European Biochemical Societies.

引用

页码：571 / 575

页数：5

共 33 条

[1] The NADH-dependent Fe3+-chelate reductases of tomato roots [J].