Characterization and localization of an iron-binding 18-kDa glycopeptide isolated from the N-terminal half of human lactotransferrin.
Mild treatment of iron-saturated human lactotransferrin by trypsin at pH 8.2 cleaves the molecule into a N-tryptic (Mr approximately equal to 30000) and a C-tryptic (Mr approximately equal to 50000) fragment, which have been isolated. Each of them carries a glycan moiety and keeps the property to bind reversibly one Fe3+. The N-tryptic fragment has been submitted to a second tryptic digestion which led to an iron-binding glycopeptide fragment with a molecular weight of about 18500. This fragment, the smallest iron-binding peptide isolated up to now from a transferrin, includes the ND2 domain of human lactotransferrin.
D002241:Carbohydrates / Q000032:analysis; D006020:Glycopeptides / Q000302:isolation & purification*; D006801:Humans; D007501:Iron / Q000032:analysis / Q000378:metabolism*; D007700:Kinetics; D007781:Lactoferrin / Q000378:metabolism*; D007782:Lactoglobulins / Q000378:metabolism*; D008970:Molecular Weight; D010446:Peptide Fragments / Q000302:isolation & purification; D013053:Spectrophotometry; D014357:Trypsin
D002241:Carbohydrates; D006020:Glycopeptides; D007782:Lactoglobulins; D010446:Peptide Fragments; D007501:Iron; D007781:Lactoferrin; D014357:Trypsin