caa a22 4500 397522800 CHVBK 20180308164637.0 cr unu---uuuuu 161202e199509 xx s 000 0 eng 10.1093/jxb/46.special_issue.1301 doi (NATIONALLICENCE)oxford-10.1093/jxb/46.special_issue.1301 The rate constant for the reaction of CO2 with enzymebound ribulose 1,5-bisphosphate in vivo [Elektronische Daten] [Juta Viil, Tut Pärnik] The partial reactions during carboxylation of ribulose-1,5-bisphosphate (RuBP) were studied. A method is proposed for the in vivo estimation of the rate constant for the reaction of CO2 with the ene-diol of RuBP formed in the active site of RuBP carboxylase/ oxygenase (Rubisco). The method involves a pretreatment of the leaves, in the light, with different concentrations of CO2 in nitrogen, followed by 6 s exposure to CO2-free air. Then the leaves are exposed to 14CO2 and the kinetics of 14C uptake are determined after 0.2-0.4 s. It is assumed that the mechanism is a regular bimolecular reaction with the rate linearly dependent on the concentrations of substrates. A value for the rate constant of 0.06 μM−1 s−1 was obtained, independent of the CO2 concentration during pretreatment. However, high pretreatment-[CO2] decreased the concentration of the competent RuBP-binding sites. © 1995 Oxford University Press Photosynthetic Carbon Reduction nationallicence Rubisco nationallicence carboxylation nationallicence partial reactions nationallicence rate constant nationallicence Viil Juta Institute of Experimental Biology, Estonian Academy of Sciences, Harku, Harjumaa, EE3051 Estonia aut Pärnik Tut Institute of Experimental Biology, Estonian Academy of Sciences, Harku, Harjumaa, EE3051 Estonia aut Journal of Experimental Botany Oxford University Press 46/special_issue(1995-09), 1301-1307 0022-0957 46:special_issue<1301 1995 46 exbotj https://doi.org/10.1093/jxb/46.special_issue.1301 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1093/jxb/46.special_issue.1301 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Viil Juta Institute of Experimental Biology, Estonian Academy of Sciences, Harku, Harjumaa, EE3051 Estonia aut NATIONALLICENCE 700 1- Pärnik Tut Institute of Experimental Biology, Estonian Academy of Sciences, Harku, Harjumaa, EE3051 Estonia aut NATIONALLICENCE 773 0- Journal of Experimental Botany Oxford University Press 46/special_issue(1995-09), 1301-1307 0022-0957 46:special_issue<1301 1995 46 exbotj Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford