Homogenates of rat small intestine can depolymerize macromolecular rat skin heparin (RS heparin) to products similar in size to commercial heparin [Horner (1972) Proc. Natl. Acad. Sci. U.S.A. 69, 3469–3473]. This activity is attributed to an enzyme provisionally named ‘macromolecular heparin depolymerase’. An assay for macromolecular heparin depolymerase activity in rat small intestine has been developed, based on the action of the enzyme on 35S-labelled macromolecular RS heparin. The depolymerized products are separated into two peaks by gel chromatography through columns of Bio-Gel A-15m. The amount of label in the second peak, expressed as a percentage of the total radioactivity, is the index of enzyme activity. The pH optimum was found to be 6.0 and the temperature optimum 45 degrees C. The enzyme was shown to be most stable in 50mM-Tris/maleate buffer containing 1 mM-EDTA. Macromolecular heparin depolymerase activity measured as a function of time and substrate concentration produced curves typical of an enzymic reaction. Evidence was obtained demonstrating that the activity did not originate from bacteria in the intestine. Macromolecular heparin depolymerase activity was increased by dilution and storage at 7 degrees C for 24 h. This suggests that homogenates of rat small intestine contain an unstable inhibitor of the enzyme.
Skip Nav Destination
Article navigation
June 1979
-
Cover Image
Cover Image
- PDF Icon PDF LinkFront Matter
- PDF Icon PDF LinkTable of Contents
- PDF Icon PDF LinkAdvertising
Research Article|
June 15 1979
The assay and partial characterization of macromolecular heparin depolymerase activity in rat small intestine
Publisher: Portland Press Ltd
Online ISSN: 1470-8728
Print ISSN: 0264-6021
© 1979 London: The Biochemical Society
1979
Biochem J (1979) 180 (3): 587–596.
Citation
E Young, A A Horner; The assay and partial characterization of macromolecular heparin depolymerase activity in rat small intestine. Biochem J 15 June 1979; 180 (3): 587–596. doi: https://doi.org/10.1042/bj1800587
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Could not validate captcha. Please try again.