Abstract
Enzymatic properties of phosphorylated urokinase plasminogen activator (P-uPA) (1) extracted from human carcinomatous cell line Detroit 562 cells were compared with those of non-phosphorylated uPA of urinary origin (nP-uPA). Using plasminogen as a subsrate, the Km and Kcat of P-uPA were higher than that of nP-uPA while the Kcat Km was lower. By zymography, a greater degree of plasminogen activation was observed. Concanavalin A reacted to both the enzymes. P-uPA had a low affinity for the inhibitors of plasminogen activator PAI-1 and PAI-2, and was inhibited only by the excess amounts of inhibitors. For PAI-1, the KIs of P-uPA was greater and for PAI-2, KI was higher for P-uPA. These alterations by phosphorylation enable uPA to be more efficient in a focal proteolysis through plasminogen activation.
Original language | English (US) |
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Pages (from-to) | 1473-1481 |
Number of pages | 9 |
Journal | Biochemical and Biophysical Research Communications |
Volume | 182 |
Issue number | 3 |
DOIs | |
State | Published - Feb 14 1992 |
Funding
This research is supported in part by a Grant-in-Aid (63570038) for Scientific Research fran the Ministry of Education, Science, and Culture, Japan.
ASJC Scopus subject areas
- Molecular Biology
- Biophysics
- Biochemistry
- Cell Biology