A RAPID AND SENSITIVE METHOD FOR DETERMINATION OF RELATIVE SPECIFICITY OF RUBISCO FROM VARIOUS SPECIES BY ANION-EXCHANGE CHROMATOGRAPHY

A rapid and sensitive method to determine the relative specificity (ta u) of ribulose 1,5-bisphosphate carboxylase/oxygenase (RuBisCO) using anion-exchange chromatography is described, We employed the open gas s ystem for the reaction of RuBisCO to get the most reliable CO2 and O-2 concentrations in the reaction mixture. 3-Phosphoglycerate and 2-phos phoglycolate which were formed in the RuBisCO reaction were completely separated and directly measured with anion-exchange chromatography wi thout using radioisotopes. The determination of the tau value was acco mplished in 3 h. The tau values of RuBisCO enzymes from higher land pl ants were between 90 and 96, and those from bacteria including cyanoba cterium were close to 45. These values were in agreement with previous ly reported values, The enzyme of the red macroalga Porphyra yezoensis exhibited a tau value of over 140, as expected from the reported valu e of the enzyme from the red microalga Porphyridium cruenteum. RuBisCO from the green macroalga Ulva pertusa had a tau value close to 70 and similar to that of the enzyme from the green microalga Chlamydomonas reinhardtii.