A new serine protease which preferentially recognizes p-guanidino-L-phenylalanyl residue in ascitic plasma from Ehrlich ascites tumor-bearing mice.

Abstract

A new enzyme which hydrolyzes anilide substrates of p-guanidino-L-phenylalanine in preference to those of arginine was found in the ascitic plasma from Ehrlich ascites tumor-bearing mice. The activity of this enzyme on N alpha-benzyloxycarbonyl-p-guanidino-L-phenylalanine p-nitroanilide was strongly inhibited by diisopropyl fluorophosphate and phenylmethanesulfonyl fluoride but not by sulfhydryl-reactive reagents and metal chelating agents. Peptide substrates containing p-guanidino-L-phenylalanine were hydrolyzed by this enzyme much faster than those containing arginine. These results suggest that this enzyme is a different type of serine protease from trypsin and thrombin. This enzyme was also found in the human gastric and colon cancer cells and their surrounding ascitic plasmas.

• Authors: H Tsunematsu, K Mizusaki, S Makisumi, K Okamoto, Y Tsunematsu
• Journal: Biochemical and biophysical research communications (Biochem Biophys Res Commun) Vol. 128 Issue 3 Pg. 1233-8 (May 16 1985) ISSN: 0006-291X [Print] United States
• PMID: 3890849 (Publication Type: Journal Article)

Chemical References

• Protease Inhibitors
• 4-guanidinophenylalanine
• Phenylalanine
• Arginine
• Endopeptidases
• Serine Endopeptidases

Topics

• Animals
• Arginine
• Ascites (enzymology)
• Carcinoma, Ehrlich Tumor (metabolism)
• Endopeptidases (metabolism)
• Female
• Mice
• Phenylalanine (analogs & derivatives)
• Protease Inhibitors
• Serine Endopeptidases
• Substrate Specificity