Linked Life Data

18571492

Source:http://linkedlifedata.com/resource/pubmed/id/18571492

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2008-7-30
pubmed:abstractText
Homocysteine (Hcy) is incorporated into protein via a reaction of the thioester Hcy-thiolactone with epsilon-amino group of a protein lysine residue. This reaction leads to impairment and alteration of protein's function and has been implicated in atherothrombotic disease. However, the data regarding N-linked Hcy content in proteins are limited, mostly due to a lack of facile assays. Here I describe a new sensitive assay for the determination of protein N-linked Hcy and demonstrate its utility for individual proteins and biological fluids. N-linked Hcy is liberated from proteins by acid hydrolysis and converted to Hcy-thiolactone, which is then purified and quantified by high-performance liquid chromatography on a cation exchange column. The quantification is by fluorescence after postcolumn derivatization with o-phthaldialdehyde. Using this assay, the levels of N-linked Hcy in individual pure proteins were found to vary from as high as 0.470-0.515 mol/mol protein for human and equine ferritins to as low as 0.00006 mol/mol protein for chicken lysozyme. Hemoglobins from a variety of species contained more N-linked Hcy than did corresponding albumins (0.0127-0.0828 vs. 0.0027-0.0086 mol/mol). Normal human plasma and milk were found to contain submicromolar concentrations of protein N-linked Hcy, whereas cow milk and whey contained micromolar concentrations of protein N-linked Hcy.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1096-0309
pubmed:author
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
380
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
257-61
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
New method for the determination of protein N-linked homocysteine.
pubmed:affiliation
Department of Microbiology and Molecular Genetics, UMDNJ-New Jersey Medical School, International Center for Public Health, Newark, NJ 07101, USA. jakubows@umdnj.edu
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't