Range: ±0.5 μmol/min/mg
||Grass Miscanthus giganteus
||Wang D, Portis AR Jr, Moose SP, Long SP. Cool C4 photosynthesis: pyruvate Pi dikinase expression and activity corresponds to the exceptional cold tolerance of carbon assimilation in Miscanthus x giganteus. Plant Physiol. 2008 Sep148(1):557-67PubMed ID18539777
||To test if the lower Ea of PPDK in crude extracts from M. × giganteus at low temperature is due to any inherent difference in the protein and related gene sequence differences, C4 PPDK genes from both species were cloned and expressed in Escherichia coli so that the two enzymes could be synthesized and extracted from a common background. The specific activities of purified His-tagged recombinant PPDK of M. × giganteus and maize increased with temperature from 6°C to 28°C but showed no significant difference across this range. The activity of PPDK was measured by coupling the production of PEP to NADH oxidation via PEPc and malate dehydrogenase modified from Ashton et al. (1990).
||The specific activities of PPDK of M. × giganteus and maize at 25°C were 7.3 ± 0.5 and 7.6 ± 0.4 µmol min-1 mg-1, respectively, and 3.3 ± 0.4 and 3.1 ± 0.3 µmol min-1 mg-1, respectively, at 15°C.