Thromb Haemost 1990; 63(03): 464-471
DOI: 10.1055/s-0038-1645067
Original Article
Schattauer GmbH Stuttgart

Deglycosylation Increases the Fibrinolytic Activity of a Deletion Mutant of Tissue-Type Plasminogen Activator

James Wilhelm
The Biotechnology and Microbiology Division, Wyeth-Ayerst Research, Inc., Radnor, Pennsylvania, USA
,
Narender K Kalyan
The Biotechnology and Microbiology Division, Wyeth-Ayerst Research, Inc., Radnor, Pennsylvania, USA
,
Shaw Guang Lee
The Biotechnology and Microbiology Division, Wyeth-Ayerst Research, Inc., Radnor, Pennsylvania, USA
,
Wah-Tung Hum
The Biotechnology and Microbiology Division, Wyeth-Ayerst Research, Inc., Radnor, Pennsylvania, USA
,
Ruth Rappaport
The Biotechnology and Microbiology Division, Wyeth-Ayerst Research, Inc., Radnor, Pennsylvania, USA
,
Paul P Hung
The Biotechnology and Microbiology Division, Wyeth-Ayerst Research, Inc., Radnor, Pennsylvania, USA
› Author Affiliations
Further Information

Publication History

Received 31 October 1989

Accepted after revision 26 January 1990

Publication Date:
30 June 2018 (online)

Summary

Δ2−89 t-PA is a deletion mutant lacking the finger (F) and epidermal growth factor (EGF) domains; thus, the fibrin interaction of this molecule must be mediated solely by the kringle region. In the present study, the influence of the oligosaccharide side-chains on the activity of Δ2−89 t-PA has been investigated. Δ2−89 t-PA was secreted in two forms, designated I and II, which presumably differ by the lack of one asparagine-linked oligosaccharide in the kiiugle 2 domain of form TT, Forms I and II of Δ2−89 t-PA weie puiified; form II displayed higher fibrinolytic activity than form I. When foini I was partially deglycosylated or treated to remove sialic acid, fibrinolytic activity was increased. Production of Δ2−89 in the presence of timicamycin led to secielion of a glyean-free activator with higher activity. These findings suggest that certain oligusacchaiide side chains, particularly (hose containing sialic acid, can interfere with the interaction between the kringle region of t-PA and fibrin.