A Non-radioisotopic Anion-exchange Chromatographic Method to Measure the CO2/O2 Specificity Factor for Ribulose Bisphosphate Carboxylase/Oxygenase

Abstract

A non-radioisotopic anion-exchange ion chromatographic method for measuring the carboxylation/ oxygenation specificity (τ) of ribulose 1, 5-bisphosphate carboxylase/oxygenase (RubisCO) is presented. The assay measures the amounts of fixation products at varying [CO2]/[O2] ratios to measure the relative rates of CO2 and O2 fixation reactions. The amount of 3-phosphoglycerate (3-PGA) and phosphoglycolate (PG) in the reaction mixture were measured with a conductivity detector and the specific factor was calculated using the following equations: ν c = ([3-PGA] – [PG])/2 and ν o = [PG]. By this method, specificity factors for RubisCOs were measured without using radioactive reagents. © 1996, Taylor & Francis Group, LLC. All rights reserved.