title: A study of human coagulation factor XIII A-subunit by electrospray ionisation mass spectrometry.
abstract: A study of factor XIII A-subunit has been made by electrospray ionisation mass spectrometry. Factor XIII has been isolated and rigorously purified, and the intact A-subunit protein has been analysed to confirm its molecular weight accurately for the first time. Thrombin proteolysis of the A-subunit has been monitored and the resulting cleavage products, the activated A-subunit protein and the Activation Peptide, have been analysed by electrospray ionisation mass spectrometry to confirm the site of proteolysis. Facile and rapid separation of the Activation Peptide from the activated A-subunit protein has been achieved using simple on-line separation techniques. The molecular weight measurements have been repeated numerous times to provide an indication of the precision and variability of the analyses.
authors.affiliation: Astbury Centre for Structural Molecular Biology, School of Biochemistry and Molecular Biology, The University of Leeds, Leeds LS2 9JT, UK. a.e.ashcroft@leeds.ac.uk
authors.forename: A E
authors.initials: AE
authors.lastname: Ashcroft
authors.forename: P J
authors.initials: PJ
authors.lastname: Grant
authors.forename: R A
authors.initials: RA
authors.lastname: Ariëns
mesh_terms: D006801:Humans; D006868:Hydrolysis; D036341:Intercellular Signaling Peptides and Proteins; D013058:Mass Spectrometry; D008970:Molecular Weight; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification; D013917:Thrombin / Q000494:pharmacology; D011503:Transglutaminases / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D036341:Intercellular Signaling Peptides and Proteins; D010455:Peptides; C061895:factor XIII activation peptide; D011503:Transglutaminases; D013917:Thrombin