In air-equilibrated buffers, the oxygenation to carboxylation ratio increases between 15 °C and 35 °C from

Range 0.16 to 0.35 unitless
Organism Wheat Triticum aestivum
Reference Misra JB. Integrated operation of the photorespiratory cycle and cytosolic metabolism in the modulation of primary nitrogen assimilation and export of organic N-transport compounds from leaves: a hypothesis. J Plant Physiol. 2014 Feb 15 171(3-4):319-28. doi: 10.1016/j.jplph.2013.09.008. p.322 left column bottom paragraphPubMed ID24157314
Primary Source N.P. Hall, A.J. Keys Temperature dependence of the enzymic carboxylation and oxygenation of ribulose-1,5-bisphosphate in relation to effects of temperature on photosynthesis Plant Physiol, 72 (1983), pp. 945–948PubMed ID16663143
Method Primary source abstract:"Carboxylase and oxygenase activities of ribulose bisphosphate carboxylase purified from wheat were measured over the temperature range 5 to 35 degrees C either at constant O(2) and CO(2) concentrations or where the O(2) and CO(2) simulated the concentrations in water equilibrated at each temperature with the same gaseous phase."
Comments p.322 left column bottom paragraph:"In air-equilibrated buffers, the oxygenation to carboxylation ratio increases between 15 °C and 35 °C from 0.16 to 0.35 (primary source). The reciprocal of these values (i.e., 1/0.16 and 1/0.35) gives the ratio of carboxylation to oxygenation. Accordingly, in well-watered plants, the ratio of carboxylation to oxygenation would be nearly 6.2:1 at 15 °C, 4.5:1 at 25 °C and 2.8:1 at 35 °C."
Entered by Uri M
ID 111956