Journal article
Binding of myeloperoxidase to bacteria: effect on hydroxyl radical formation and susceptibility to oxidant-mediated killing
Biochimica et biophysica acta. General subjects, Vol.1290(3), pp.231-240
1996
DOI: 10.1016/0304-4165(96)00014-1
PMID: 8765125
Abstract
Neutrophils form superoxide anion (O
2
·−) and hydrogen peroxide (H
2O
2) and release myeloperoxidase (MPO) during ingestion of microbial pathogens. MPO, which adheres to some bacteria, catalyzes the formation of HOCI from H
2O
2, thereby enhancing
H
2
O
2
O
2
·−
microbicidal activity. Hydroxyl radical (HO
·), also is an important contributor to H
2O
2 and O
2
·− microbicidal activity. MPO decreases iron-catalyzed HO
· production but also leads to HO
· production through the reaction of O
2
·− and HOCl. We hypothesized that binding of MPO to bacteria could alter the magnitude and site of HO
· production upon organism exposure to O
−
2/H
2O
2. Incubation of MPO with
Escherichia coli and
Pseudomonas aeruginosa resulted in stable association of MPO with the bacteria which enhanced their susceptibility to killing by
O
2
·−
H
2
O
2
. In the absence of MPO preincubation exposure of
E. coli, but not
P. aeruginosa to
O
2
·−
H
2
O
2
led to iron-catalyzed HO
· generation. This was associated with different amounts of redox active iron in the two types of bacteria. MPO preincubation slightly decreased HO
· detected with
E. coli, but markedly increased HO
· formation with
P. aeruginosa. This likely resulted from decreased iron-catalyzed HO
· production counterbalanced by increased iron-independent HO
· formation. MPO preincubation did not effect bacterial killing by a system which generated only H
2O
2, precluding MPO-dependent HO
· formation. These data are consistent with a possible role for MPO-derived HO
· in the augmentation of bacterial killing by this enzyme.
Details
- Title: Subtitle
- Binding of myeloperoxidase to bacteria: effect on hydroxyl radical formation and susceptibility to oxidant-mediated killing
- Creators
- Bradley E Britigan - Department of Internal Medicine and Research Service, VA Medical Center, Iowa City, IA, USAHeather R Ratcliffe - Department of Internal Medicine and Research Service, VA Medical Center, Iowa City, IA, USAGarry R Buettner - Department of ESR Facility, The University of Iowa College of Medicine, Iowa City, IA, USAGerald M Rosen - VA Medical Center, Baltimore, MD, USA
- Resource Type
- Journal article
- Publication Details
- Biochimica et biophysica acta. General subjects, Vol.1290(3), pp.231-240
- Publisher
- Elsevier B.V
- DOI
- 10.1016/0304-4165(96)00014-1
- PMID
- 8765125
- ISSN
- 0304-4165
- eISSN
- 1872-8006
- Language
- English
- Date published
- 1996
- Academic Unit
- Radiation Oncology
- Record Identifier
- 9984047758102771
Metrics
26 Record Views