Relative initial rates of deamination of adenosine and AMP for each deaminase.

The deamination was measured by loss of OD265 in 10 mM Tris-HCl pH 7.5, 1 mM EDTA, 50 mM NaCl buffer. The substrate concentrations were 100 μM for the HPAMPD and A. californica enzymes and 2 mM for the human enzyme. The reaction temperature for H. pomatia and A. californica ADGFs was 25° and 37° for human ADGF. All values were obtained with recombinant enzymes except for the value in parentheses which was obtained with the native preparation of HPAMPD.