Phosphate ester hydrolysis is catalyzed by a bacterial transferrin: potential implications for in vivo iron transport mechanisms

Two synergistic anions, p-nitrophenyl phosphate ester ( NPP ) and SO 4 2 - , were found to form new stable assemblies with Fe 3+ and a bacterial transferrin, FbpA (FbpA = ferric binding protein). Fe 3+FbpA–SO 4 undergoes rapid anion exchange in the presence of NPP to form Fe 3+FbpA–NPP. Formation of...

Full description

Saved in:
Bibliographic Details
Published in:Journal of inorganic biochemistry 2004-11, Vol.98 (11), p.1975-1977
Main Authors: Dhungana, Suraj, Anderson, Damon S., Mietzner, Timothy A., Crumbliss, Alvin L.
Format: Article
Language:English
Subjects:
Anions
Carrier Proteins - chemistry
Carrier Proteins - metabolism
Catalysis
Ferric binding protein
Hydrolysis
Iron
Iron - chemistry
Organophosphates - chemistry
Periplasm
Phosphatase
Polyphosphate
Spectrophotometry
Sulfates - chemistry
Transferrin - metabolism
Transport
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Two synergistic anions, p-nitrophenyl phosphate ester ( NPP ) and SO 4 2 - , were found to form new stable assemblies with Fe 3+ and a bacterial transferrin, FbpA (FbpA = ferric binding protein). Fe 3+FbpA–SO 4 undergoes rapid anion exchange in the presence of NPP to form Fe 3+FbpA–NPP. Formation of Fe 3+FbpA–NPP was found to accelerate the rate of hydrolysis of the bound phosphate ester ( k hyd = 1.6 × 10 −6 s −1 at 25 °C and pH 6.5) by >10 3 fold over the uncatalyzed reaction. These findings suggest a dual function for FbpA in vivo: transport of Fe 3+ across the periplasmic space to the inner membrane in certain gram-negative bacteria and hydrolysis of periplasmic polyphosphates.
ISSN:0162-0134
1873-3344
DOI:10.1016/j.jinorgbio.2004.08.004