Evaluation of immobilized boronates for studies of adenine and pyridine nucleotide metabolism

Three different immobilized boronates were compared with respect to their possible utility in studies of adenine and pyridine nucleotide metabolism. These included boronate derivatives of polyacrylamide, Sepharose, and the cation-exchange resin, Bio-Rex 70. The relative binding affinities, binding capacities, and elution properties were compared. Under the conditions utilized, the Sepharose and Bio-Rex 70 derivatives selectively retained nucleotides containing two or more sets of 1,2 cis-diol groups. Since the bulk of cellular nucleic acids contain but a single set of 1,2 cis-diol groups or less, these boronate derivatives are very useful for the isolation of the acid-soluble nucleotides, NAD and diadenosine 5',5"'-tetraphosphate, and for the acid-insoluble polymer, poly(ADP-ribose). The Bio-Rex 70 derivative had a particularly useful combination of binding selectivity, capacity, and elution characteristics. Specific applications of this resin for studies of NAD and poly(ADP-ribose) metabolism are presented.