Purification and biochemical characterisation of a glucose-6-phosphate dehydrogenase from the psychrophilic green alga Koliella antarctica

摘要: Psychrophilic organisms have evolved a number of modifications cellular structures to survive in the cold environment; among them it is worth noting an increased efficiency enzymes at lower temperatures. Glucose-6-phosphate dehydrogenase (G6PDH; EC 1.1.1.49) was purified and characterised from psychrophilic green alga Koliella antarctica (Trebouxiophyceae, Chlorophyta) Ross Sea (Antarctica). It possible isolate single G6PDH using biochemical strategies; its maximum activity measured 35 °C, enzyme showed Ea 39.6 kJ mol−1. This protein reacted with antibodies raised against higher plants plastidic isoforms. KaG6PDH peculiar kinetic properties, KiNADPH value than \( K_{{{\text{mNADP}}^{ + } }} \). Notably, catalytic inactivated vitro by DTT chloroplastic thioredoxin f. These properties are discussed respect plant G6PDHs adaptation K. polar low-temperature environment.