Linked Life Data

16483534

Source:http://linkedlifedata.com/resource/pubmed/id/16483534

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
2006-9-29
pubmed:abstractText
The phagocyte NADPH oxidase produces superoxide anion (O(2)(.-)) by the electrogenic process of moving electrons across the cell membrane. This charge translocation must be compensated to prevent self-inhibition by extreme membrane depolarization. Examination of the mechanisms of charge compensation reveals that these mechanisms perform several other vital functions beyond simply supporting oxidase activity. Voltage-gated proton channels compensate most of the charge translocated by the phagocyte NADPH oxidase in human neutrophils and eosinophils. Quantitative modeling of NADPH oxidase in the plasma membrane supports this conclusion and shows that if any other conductance is present, it must be miniscule. In addition to charge compensation, proton flux from the cytoplasm into the phagosome (a) helps prevent large pH excursions both in the cytoplasm and in the phagosome, (b) minimizes osmotic disturbances, and (c) provides essential substrate protons for the conversion of O(2)(*-) to H(2)O(2) and then to HOCl. A small contribution by K+ or Cl- fluxes may offset the acidity of granule contents to keep the phagosome pH near neutral, facilitating release of bactericidal enzymes. In summary, the mechanisms used by phagocytes for charge compensation during the respiratory burst would still be essential to phagocyte function, even if NADPH oxidase were not electrogenic.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:volume
1757
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
996-1011
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Charge compensation during the phagocyte respiratory burst.
pubmed:affiliation
Department of Molecular Biophysics and Physiology, Rush University Medical Center, Chicago, IL 60612, USA.
pubmed:publicationType
Journal Article, Review, Research Support, N.I.H., Extramural