The haemoglobin-like protein (HMP) of Escherichia coli has ferrisiderophore reductase activity and its C-terminal domain shares homology with ferredoxin NADP+ reductases.
Three soluble ferrisiderophore reductases (FsrA, FsrB and FsrC) were detected in Escherichia coli. FsrB was purified and identified as the haemoglobin-like protein (HMP) by size and N-terminal sequence analyses. HMP was previously isolated as a dihydropteridine reductase and is now shown to have ferrisiderophore reductase activity. Database searches revealed that the C-terminal region of HMP (FsrB) is homologous to members of a family of flavoprotein oxidoreductases which includes ferredoxin NADP+ reductase (FNR). The combination of FNR-like and haemoglobin-like regions in HMP (FsrB) represents a novel pairing of functionally and structurally distinct domains. Structure-function properties of other FNR-like proteins, including LuxG and VanB, are also discussed.
Andrews
S C
SC
Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, UK.
Shipley
D
D
Keen
J N
JN
Findlay
J B
JB
Harrison
P M
PM
Guest
J R
JR
D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016974:Dickeya chrysanthemi / Q000235:genetics; D004093:Dihydropteridine Reductase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000737:chemistry* / Q000201:enzymology; D029968:Escherichia coli Proteins; D005287:Ferredoxin-NADP Reductase / Q000737:chemistry*; D005798:Genes, Bacterial; D006420:Hemeproteins; D009247:NADH, NADPH Oxidoreductases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D010446:Peptide Fragments / Q000737:chemistry; D011487:Protein Conformation; D012486:Salmonella typhimurium / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D006420:Hemeproteins; D010446:Peptide Fragments; D005287:Ferredoxin-NADP Reductase; D004093:Dihydropteridine Reductase; C076538:hmp protein, E coli; D009247:NADH, NADPH Oxidoreductases; C024253:ferrisiderophore reductase