This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Yokota, A. Articles by Canvin, D. T. Search for Related Content PubMed PubMed Citation Articles by Yokota, A. Articles by Canvin, D. T. Agricola Articles by Yokota, A. Articles by Canvin, D. T.

Articles

Changes of Ribulose Bisphosphate Carboxylase/Oxygenase Content, Ribulose Bisphosphate Concentration, and Photosynthetic Activity during Adaptation of High-CO₂ Grown Cells to Low-CO₂ Conditions in Chlorella pyrenoidosa¹

Department of Biology, Queen's University, Kingston, Ontario, Canada K7L 3N6

Changes of some photosynthetic properties of high-CO₂ grown cells of Chlorella pyrenoidosa during adaptation to low-CO₂ conditions have been investigated. The K_m value of photosynthesis of the high-CO₂ grown cells for dissolved inorganic carbon was 3.3 millimolar and decreased to 25 to 30 micromolar within 4 hours after transferring to air. In the presence of saturating CO₂ concentrations the photosynthetic activity of the high-CO₂ grown cells was 1.5 times as high as that of the low-CO₂ grown cells. There was a significant rise of the photosynthetic activity during adaptation of the high-CO₂ grown cells to air, followed by a steady decrease. The activity of ribulose 1,5-bisphosphate carboxylase/oxygenase in both the high- and low-CO₂ grown cells was close to the photosynthetic activity of the cells. The concentration of ribulose 1,5-bisphosphate (RuBP) was higher in the low-CO₂ adapting and low-CO₂ grown cells than in the high-CO₂ grown cells regardless of the photosynthetic rate. This seems to be due to an increased RuBP regeneration activity during adaptation followed by maintenance of the new higher concentration. The RuBP level always exceeded the concentration of ribulose 1,5-bisphosphate carboxylase/oxygenase RuBP binding sites in both the high- and low-CO₂ grown cells at any dissolved inorganic carbon concentration.

¹ Supported by the Natural Sciences and Engineering Research Council of Canada.

This article has been cited by other articles:

				Y. Yabuta, M. Tamoi, K. Yamamoto, K.-i. Tomizawa, A. Yokota, and S. Shigeoka Molecular Design of Photosynthesis-Elevated Chloroplasts for Mass Accumulation of a Foreign Protein Plant Cell Physiol., March 1, 2008; 49(3): 375 - 385. [Abstract] [Full Text] [PDF]

				H. Eichelmann and A. Laisk Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase Content, Assimilatory Charge, and Mesophyll Conductance in Leaves Plant Physiology, January 1, 1999; 119(1): 179 - 190. [Abstract] [Full Text]