A carbon dioxide concentrating system in leaves of higher 3 carbon pathway plants predicted by a model based on rubidium bisphosphate carboxylase oxygenase kinetics and carbon 14 dioxide carbon 12 dioxide exchange
Machler, F.; Lehnherr, B.; Schnyder, H.; Nosberger, J.
Journal of Experimental Botany 36(171): 1542-1550
ISSN/ISBN: 0022-0957 Accession: 004549334
A model is presented which compares the ratio of the 2 activities of the enzyme ribulose bisphosphate carboxylase/oxygenase as determined in vitro with the ratio of photosynthesis to photorespiration in leaves as determined from differential 14CO2/12CO2 uptake or from CO2 compensation concentration. Discrepancies between measurements made in vitro and in vivo are attributed to the effect of a CO2 concentrating system in the leaf cells. Interference from dark respiration is discussed. A CO2 concentrating system is postulated which is efficient mainly at low temperature and low CO2 concentration.