Activity of ribulose 1,5-bisphosphate carboxylase oxygenase as a function of storage conditions

Abstract

Optimal storage conditions to retain ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) activity were investigated. The soluble spinach (Spinacia oleracea) enzyme was pretreated with its activators, Mg2+ and HCO3-, and then stored for up to 30 days at 4 or -18°C or in liquid N2. Cold inactivation and conformational changes were suggested to be involved during Rubisco storage in the cold, leading to its inactivation. Pretreatment of the enzyme with Mg2+ and CO2 and subsequent storage at either 4°C or in liquid N2 or flushing the samples with N2 and rapid freezing and storage in liquid N2 are recommended as storage procedures. These storage treatments will prevent inactivation, so that full original specific activity will be preserved.