Purification and characterization of altered cystic fibrosis liver alpha-L-fucosidase.

alpha-L-Fucosidase (E.C.3.2.4.51) from two cystic fibrosis livers has been purified and characterized. Purification was accomplished by an affinity chromatographic procedure previously used for normal liver alpha-L-fucosidase. Characterization of the two cystic fibrosis alpha-L-fucosidases indicated that they were very similar to normal liver alpha-L-fucosidase with regard to pH optima profiles, Michaelis constants (Km's), subunit structure and antigenicity. However, gas liquid chromatographic analysis revealed altered carbohydrate compositions for both the cystic fibrosis alpha-L-fucosidases. The three major sugars found in normal purified liver alpha-L-fucosidase (mannose, N-acetylglucosamine and sialic acid) were reduced in the cystic fibrosis alpha-L-fucosidases, on average, to 51%, 44% and 32%, respectively, of their normal amounts.