The influence of pyridoxal-5′-phosphate on the temperature relationship of aspartate aminotransferase and alanine aminotransferase has been determined. On varying the reaction temperature from 25° to 45° both enzymes showed small but significant deviations from a linear Arrhenius relationship. Supplementation with pyridoxal-5′-phosphate in general enhanced the catalytic activity to the same degree over the entire temperature range. Our results corroborate the findings of Rej but not those of Jung et al.
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