New method to discriminate between cathepsin B and cathepsin L in crude extracts from fish muscle based on a simple acidification procedure

Authors: Godiksen, Helene; Nielsen, Henrik Hauch

Source: International Journal of Food Science & Technology, Volume 42, Number 1, January 2007 , pp. 102-106(5)

Buy & download fulltext article:

Price: $48.00 plus tax (Refund Policy)

Abstract:

Summary

A new and simple method to distinguish between cathepsin B and cathepsin L in crude extracts of herring (Clupea harengus) muscle has been established. An acid treatment of crude extracts (exposed to pH 3 for 5 min) activated a latent form of cathepsin L and inactivated cathepsin B. Furthermore, in neutral crude extract, the hydrolysis of benzyloxycarbonyl-l-phenylalanyl-l-arginyl-4-methylcoumarine (Z-Phe-Arg-MCA) (cathepsin B and cathepsin L substrates) was between 0% and 15% of the hydrolysis of benzyloxycarbonyl-l-arginyl-l-arginyl-7-amino-4-methylcoumarine (Z-Arg-Arg-MCA; cathepsin B substrate). Cathepsin B activity is measured in neutral extract using the specific cathepsin B substrate Z-Arg-Arg-MCA and cathepsin L activity is measured in acid-treated extract with Z-Phe-Arg-MCA as substrate. The specific cathepsin B inhibitor, CA-074, did not inhibit the Z-Arg-Arg-MCA significantly without affecting the Z-Phe-Arg-MCA activity. An acid treatment of the crude extract is therefore a more advantageous approach to discriminate between cathepsin B and cathepsin L activities.

Keywords: Acid activation; cathepsin B; cathepsin L; crude extract; herring; inhibitor CA-074

Document Type: Research article

DOI: http://dx.doi.org/10.1111/j.1365-2621.2006.01254.x

Publication date: 2007-01-01