Linked Life Data

16331960

Source:http://linkedlifedata.com/resource/pubmed/id/16331960

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
49
pubmed:dateCreated
2005-12-7
pubmed:abstractText
Transferrin exhibits heterogeneity in glycosylation characteristic of pathological changes in alcohol abuse and congenital disorders in glycosylation. This study investigated an alternative approach in the detection of carbohydrate-deficient transferrin based on the premise that glycosylation may afford some degree of protection to proteolytic action. Differential susceptibility to proteolysis by chymotrypsin was demonstrated for normal glycosylated and nonglycosylated recombinant human transferrin, using reverse-phase (RP) HPLC, matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry, and LC-tandem mass spectrometry (MS/MS). Peptide fragmentation profiles were consistent with a predominantly high-specificity cleavage pattern of chymotrypsin. The observed peptide fragmentation profile showed that the C-lobe of recombinant full-length nonglycosylated transferrin (rhTf-NG) appeared to be preferentially cleaved, while cleavage of the N-lobe was restricted to the N-terminal and link sequence regions. Although chymotryptic cleavage sites abound in the N-lobe, their resistance to cleavage was independent of glycosylation. Compared to previous studies of lactoferrin, our data suggest disparity in the role by which glycosylation exerts a protective effect in the siderophilin family. It was clear from the transferrin digestions analyzed by HPLC that N-linked glycosylation did confer protection from proteolysis by chymotrypsin. After fragmentation, a range of peptides representing previously cryptic epitopes were identified as potential candidates for an immunological approach to differentiate between the different transferrin glycoforms. Based on its proximity to the Asn413 glycosylation site, a 15-mer peptide, m/z 1690.472 (NKSDNCEDTPEAGYF), was identified as a suitable candidate for raising anti-peptide antibodies for subsequent immunological detection. This novel approach could form the basis for an alternative assay or reference method for the detection of carbohydrate-deficient transferrin.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
13
pubmed:volume
44
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
16007-13
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Differential susceptibility of transferrin glycoforms to chymotrypsin: a proteomics approach to the detection of carbohydrate-deficient transferrin.
pubmed:affiliation
Department of Clinical Chemistry, Biomedicum, University of Helsinki, PB 63, Haarmaninkatu 8, FIN-00014, Finland.
pubmed:publicationType
Journal Article