Affiliation:
1. Biological and Agricultural Engineering Department, Driftmier Engineering Center, University of Georgia, Athens, Georgia 30602
Abstract
ABSTRACT
Major pyoverdines from
Pseudomonas fluorescens
2-79 (Pf-B),
P. aeruginosa
ATCC 15692 (Pa-C), and
P. putida
ATCC 12633 (Pp-C) were examined by absorption and fluorescence spectroscopic techniques to investigate the interaction between ferrous ion and the pyoverdine ligand. At physiological pH, ferrous ion quenched the fluorescence of all three pyoverdines much faster than ferric ion did. Also, increased absorbance at 460 nm was observed to be much faster for Fe
2+
-pyoverdine than for Fe
3+
-pyoverdine. At pH 7.4, about 90% of Fe
3+
was bound by pyoverdine Pa-C after 24 h whereas Fe
2+
was bound by the pyoverdine completely in only 5 min. The possibility that Fe
2+
underwent rapid autoxidation before being bound by pyoverdine was considered unlikely, since the Fe
2+
concentration in pyoverdine-free samples remained constant over a 3-min period at pH 7.4. Incubating excess Fe
2+
with pyoverdine in the presence of 8-hydroxyquinoline, an Fe
3+
-specific chelating agent, resulted in the formation of a Fe
3+
-hydroxyquinoline complex, suggesting that the iron in the Fe
2+
-pyoverdine complex existed in the oxidized form. These results strongly suggested that pyoverdines bind and oxidize the ferrous ion.
Publisher
American Society for Microbiology
Subject
Ecology,Applied Microbiology and Biotechnology,Food Science,Biotechnology
Reference25 articles.
1. Role of iron in bacterial infection.;Bullen J. J.;Curr. Top. Immunol.,1978
2. Spectrophotometric determination of serum iron at the submicrogram level with a new reagent (ferrozine).;Carter P.;Anal. Biochem.,1971
3. Dean
J. A.
Lange’s handbook of chemistry
1985
5
82
McGraw-Hill Book Co.
New York N.Y
4. Demange
P.
Wendenbaum
S.
Bateman
A.
Dell
A.
Abdallah
M. A.
Bacterial siderophores: structure and physicochemical properties of pyoverdines and related compounds
Iron transport in microbes plants and animals.
Winkelmann
G.
van der Helm
D.
Neilands
J. B.
1987
167
187
VCH Verlagsgesellschaft
Weinheim Germany
5. Pseudomonas siderophores: structure and physicochemical properties of pyoverdins and related peptides.;Demange P.;Colloq. INSERM.,1989
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