Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2007-8-27
pubmed:abstractText
The arginine- and lysine-specific gingipains of Porphyromonas gingivalis have been implicated in the degradation of haemoglobin from which the black mu-oxo haem dimer-containing pigment is generated. Here, we examined interactions of oxyhaemoglobin (oxyHb) with the Arg-(R)-specific (HRgpA) and Lys-(K)-specific (Kgp) gingipains. Incubation of oxyHb with HRgpA resulted in formation of methaemoglobin (metHb), which could be prevented by the R-gingipain specific inhibitor leupeptin. oxyHb-Kgp interactions resulted in formation of a haemoglobin haemichrome. This was inhibited by the lysine-specific protease inhibitor Z-Phe-Lys-acyloxymethylketone (Z-FKck). metHb, formed by treatment of oxyHb with either NaNO(2) or by pre-incubation with HRgpA, was rapidly degraded by Kgp compared to oxyHb. metHb degradation by Kgp was also inhibited Z-FKck. Together these data show that R-gingipain activity is crucial for converting oxyHb into the metHb form which is rendered more susceptible to Kgp degradation for the eventual release of iron(III) protoporphyrin IX and production of the mu-oxo haem dimer. This explains previous observations [J.W. Smalley, M.F. Thomas, A.J. Birss, R. Withnall, J. Silver, Biochem. J. 379 (2004) 833-840.] of the requirement for a combination of both R- and K-gingipains for pigment production from oxyhaemoglobin by P. gingivalis.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0003-9861
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
465
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
44-9
pubmed:dateRevised
2007-12-3
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Sequential action of R- and K-specific gingipains of Porphyromonas gingivalis in the generation of the haem-containing pigment from oxyhaemoglobin.
pubmed:affiliation
Department of Clinical Dental Sciences, The University of Liverpool, Liverpool, UK. josmall@liv.ac.uk
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural