Free flavins accelerate release of ferrous iron from iron storage proteins by both free flavin-dependent and -independent ferric reductases in Escherichia coli

被引：8

作者：

Satoh, Junichi ^{[1
]}

Kimata, Shinya ^{[1
]}

Nakamoto, Shota ^{[1
]}

Ishii, Tatsuya ^{[1
]}

Tanaka, Eisuke ^{[1
]}

Yumoto, Sayuri ^{[1
]}

Takeda, Kouji ^{[2
]}

Yoshimura, Etsuro ^{[3
]}

Kanesaki, Yu ^{[4
]}

Ishige, Taichiro ^{[4
]}

Tanaka, Keisuke ^{[4
]}

Abe, Akira ^{[5
]}

Kawasaki, Shinji ^{[1
]}

Niimura, Youichi ^{[1
]}

机构：

[1] Tokyo Univ Agr, Dept Biosci, Tokyo, Japan

[2] Tokyo Univ Agr, Educ Course, Tokyo, Japan

[3] Open Univ Japan, Chiba, Japan

[4] Tokyo Univ Agr, Nodai Genome Res Ctr, Tokyo, Japan

[5] Sapporo Med Univ, Dept Ophthalmol, Sapporo, Hokkaido, Japan

来源：

JOURNAL OF GENERAL AND APPLIED MICROBIOLOGY | 2019年 / 65卷 / 06期

关键词：

Escherichia coli; ferric reductase; ferritin; flavin reductase; free flavin; iron; iron storage protein; PSEUDOMONAS-AERUGINOSA; SULFITE REDUCTASE; OXIDOREDUCTASE; MOBILIZATION; GENERATION;

D O I：

10.2323/jgam.2019.03.001

中图分类号：

Q81 [生物工程学（生物技术）]; Q93 [微生物学];

学科分类号：

071005 ; 0836 ; 090102 ; 100705 ;

摘要：

Ferredoxin NADP(+) oxidoreductase (Fpr) and oxygen-insensitive NAD(P)H nit roreductase (NfnB) are purified from Escherichia coli JM109 (E. coli JM109) as a predominant free flavin-independent ferric reductase. In the present study, we prepared natural iron storage proteins, E. coli ferritin A (FtnA) and bacterinferritin (Bfr), to show the effective ferrous iron release from these proteins by Fpr and NfnB in the presence of free flavins. Fpr and NfnB showed flavin reductase activity for flayin adenine dinucleotide (FAD), flavin mononucleotide (FMN) and riboflavin, and their ferrous iron release activities were positively associated with the catalytic efficiencies (k(cat)/K-m) for individual flavins. The ferrous iron release activity of E. coli cell-free extracts was affected by flavin reductase activity of the extracts. The Butyl TOYOPEARL column chromatography of the extracts, on the basis of NAD (P)H-dependent flavin reductase activity, resulted in the separation of six active fractions containing Fpr, NfnB, NAD(P)H-quinone oxidoreductase (QOR), flavin reductase (Fre) or alkyl hydroperoxide reductase subunit F (AhpF) as major components. Like Fpr and NfnB, recombinant QOR, Fre, and AhpF showed flavin reductase activity and ferrous iron release activity in the presence of free flavins, indicating an association of flavin reductase activity with ferrous iron releasing activity. Taken together, both free flavin-dependent and free flay in-independent ferric reductases in E. coli require free flavins to mediate an electron transfer from NAD(P)H to ferric iron in the iron storage proteins for the effective ferrous iron release.

引用

页码：308 / 315

页数：8