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 Moore, B. d. Articles by Seemann, J. R. Search for Related Content PubMed PubMed Citation Articles by Moore, B. d. Articles by Seemann, J. R. Agricola Articles by Moore, B. d. Articles by Seemann, J. R.

Metabolism and Enzymology

Identification and Levels of 2'-Carboxyarabinitol in Leaves ¹

Department of Biochemistry, University of Nevada, Reno, Nevada 89557-0014, Department of Botany, University of Wisconsin, Madison, Wisconsin 53706

2'-Carboxyarabinitol 1-phosphate (CA1P) is a naturally occurring inhibitor of ribulose-1,5 bisphosphate carboxylase/oxygenase activity. A chloroplast phosphatase has previously been identified that degrades CA1P in vitro to carboxyarabinitol (CA) plus phosphate, but CA has not yet been detected in plants. Here, we detail procedures to isolate and assay CA from leaves and utilize mass spectrometry to demonstrate for the first time that CA is present in plants. CA was present in leaves of all 13 species examined, including those of C₃, C₄, and Crassulacean acid metabolism photosynthetic subgroups. CA was present both in species with high levels of CA1P (e.g. Phaseolus vulgaris, Lycopersicon esculentum, Beta vulgaris) as well as in species with low levels of CA1P (e.g. Spinacea oleracea, Triticum aestivum). CA levels in the light were sometimes greater than those in the dark. Bean leaves had the most CA of any species tested, with levels in the light approaching 1 micromole per milligram of chlorophyll. In illuminated bean leaves, about 63% of the CA is located outside the chloroplast. CA is one of only a few branched chain sugar acids to be identified from plants.

This article has been cited by other articles:

				P. J. Andralojc, A. J. Keys, J. Kossmann, and M. A. J. Parry Elucidating the biosynthesis of 2-carboxyarabinitol 1-phosphate through reduced expression of chloroplastic fructose 1,6-bisphosphate phosphatase and radiotracer studies with 14CO2 PNAS, March 21, 2002; (2002) 72137099. [Abstract] [Full Text] [PDF]

				P. J. Andralojc, A. J. Keys, W. Martindale, G. W. Dawson, and M. A.J. Parry Conversion of D-Hamamelose into 2-Carboxy-D-arabinitol and 2-Carboxy-D-arabinitol 1-Phosphate in Leaves of Phaseolus vulgaris L. J. Biol. Chem., October 25, 1996; 271(43): 26803 - 26809. [Abstract] [Full Text] [PDF]

				P. J. Andralojc, A. J. Keys, J. Kossmann, and M. A. J. Parry Elucidating the biosynthesis of 2-carboxyarabinitol 1-phosphate through reduced expression of chloroplastic fructose 1,6-bisphosphate phosphatase and radiotracer studies with 14CO2 PNAS, April 2, 2002; 99(7): 4742 - 4747. [Abstract] [Full Text] [PDF]