Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2007-2-28
pubmed:abstractText
We have developed a new strategy to enrich and fractionate phosphopeptides from peptide mixtures based on the difference in their isoelectric points (pIs) after methyl esterification. After isoelectric focusing (IEF) of a methylated tryptic digest of a mixture of alpha-S-casein and beta-casein, phosphopeptides were selectively enriched at acidic and neutral pHs while nonphosphopeptides left the focusing gel because their pIs are higher than the upper limit of the immobilized pH gradient. We wrote a web-based program, pIMethylation, to predict the pIs for peptides with and without methyl esterification. Theoretical calculations using pIMethylation indicated that methylated phosphopeptides and non-phosphopeptides can be grouped on the basis of the number of phosphate groups and basic residues in each peptide. Our IEF results were consistent with theoretical pIs of methylated peptides calculated by pIMethylation. We also showed that 2,6-dihydroxy-acetophenone is superior to 2,5-dihydroxybenzoic acid as a matrix for MALDI Q-TOF MS of methylated phosphopeptides in both positive and negative ion modes.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-11028642, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-14987115, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-14998171, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-14998538, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-15215467, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-15302935, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-15373450, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-15373456, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-15672457, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-15753120, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-15858219, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-15880631, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-15889909, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-16159144, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-16222723, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-16396503, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-16536406, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-16849286, http://linkedlifedata.com/resource/pubmed/commentcorrection/17249638-8125050
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0003-2700
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
79
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2007-14
pubmed:dateRevised
2011-9-26
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Selective enrichment and fractionation of phosphopeptides from peptide mixtures by isoelectric focusing after methyl esterification.
pubmed:affiliation
Department of Pharmacology and Skirball Institute of Biomolecular Medicine, and Department of Biochemistry, NYU School of Medicine, New York, New York 10016, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural