Brain myo-inositol monophosphatase: activity of the single subunit in a dimeric enzyme

Reversible dissociation of the dimeric structure of brain myo-inositol monophosphatase into subunits was attained by the addition of guanidine-HCl (4M). The molecular mass of the subunits (29 KDa) was determined by HPLC chromatography. Separation of the processes of refolding and association of the monomeric species was achieved by attaching the protein subunits to a rigid matrix (Affi-gel 15). The matrix-bound monomer is determined to be catalytically active, indicating that monomeric subunit of the phosphate is capable of conducting independent catalysis.