M. Swiatkowska et al., EXPRESSION OF A HUMAN PAI-1 FUSION PEPTIDE IN ESCHERICHIA-COLI AND ITS IMMUNOCHEMICAL CHARACTERIZATION, Fibrinolysis, 8(3), 1994, pp. 177-181
A peptide fragment Gly(173)-Thr(232) of human plasminogen activator in
hibitor (PAI-1) corresponding to beta-ribbon 3A and 3C-4C in the molec
ule was synthesized as a fusion protein with beta-galactosidase Met(1)
-Val(441) in E. coli. The peptide fragment was then isolated by HPLC f
rom cleavage products obtained after treatment of the purified fusion
protein with hydroxylamine. Specific antibodies reacting with epitopes
present in PAI-1((173-232)) were then used to characterize the locati
on of these epitopes in the intact PAI-1 molecule. It was found that s
ome epitopes of the synthetic fragment are not expressed by intact PAI
-1 indicating that this hydrophilic segment is partially hidden in lat
ent form of PAI-1.