An altered hexosaminidase A in the liver affected by Hurler and Hunter syndromes.

Total hexosaminidase (Hex) in the liver obtained from Hurler and Hunter syndromes displayed about ten times higher activity than that in control liver and moreover, its thermostability was significantly increased. On DEAE cellulose column chromatography, Hex A in the liver of those patients was eluted at much higher salt concentration than that required for elution of Hex A from control liver. There was no difference in elution patterns of Sephadex G-200 and Concanavalin A-Sepharose column chromatographies between the altered Hex A and control Hex A. It appears that the glycosaminoglycans accumulating in the liver of those patients are partly bound to Hex A, and that this binding may cause some changes of its properties such as ionic charge and thermostability.