Biosynthesis of heparan sulfate |
| |
Authors: | Jeremiah E Silbert Clinton T Baldwin |
| |
Institution: | (1) Connective Tissue-Aging Research Laboratory, Veterans Administration Outpatient Clinic, 17 Court Street, 02108 Boston, MA;(2) Department of Medicine, Harvard Medical School, USA Boston, MA |
| |
Abstract: | Microsomal preparations from Englebreth-Holm-Swarm mouse sarcoma were incubated with UDP-N-acetyl3H] glucosamine and UDP-14C]glucuronic acid to form proteoglycan containing 3H,14C]glycosaminoglycan with equimolar amounts of 3H]glucosamine and 14C]glucuronic acid. The labelled glycosaminoglycan was totally resistant to degradation by testicular hyaluronidase, but could be degraded readily by a crudeFlavobacter heparinum enzyme preparation which is capable of degrading heparin and heparan sulfate. Chromatography of the 3H,14C]glycosaminoglycan on DEAE-cellulose provided a pattern with three peaks: the first appearing before hyaluronic acid, the second and largest appearing at the site of hyaluronic acid, and a third appearing slightly beyond hyaluronic acid but before a standard of chondroitin sulfate. When 3 -phosphoadenosine 5 -phosphosulfate was also included in the reaction mixture, a change appeared in the 3H,14C]glycosaminoglycan so that chromatography on DEAE-cellulose presented a pattern with a significant amount of material which cochromatographed in the area where heparan sulfate would be found. There was no material that co-chromatographed with the more highly sulfated substance, heparin. This indicates that the microsomal preparation from the Englebreth-Holm-Swarm sarcoma is capable of producing a heparan sulfate-like molecule and is controlled in its sulfation of precursors so that heparin is not formed. |
| |
Keywords: | Heparan sulfate glycosaminoglycan synthesis sulfation |
本文献已被 SpringerLink 等数据库收录! |
|