ANALYSIS OF NORMAL AND MUTANT FORMS OF HUMAN ADENOSINE DEAMINASE- A REVIEW

A deficiency of the enzyme adenosine deamin-ase is associated with an autosomal recessive form of severe combined immunodeficiency dis-ease in man. The molecular forms of the normal human enzyme have now been well charac-terized in an effort to better understand the nature of the enzyme defect in affected patients. In some human tissues adenosine deaminase exists predominantly as a small molecular form while in other tissues a large form composed of adenosine deaminase (small form) and an adenosine deaminase-binding protein predomi-nates. The small form of the enzyme purified to homogeneity by antibody affinity chromatog-raphy is a monomer of native molecular weigh