PARENT SESSION
Posters P5B Light, redox and metabolic regulation: Dark Reactions. Abstracts (528-530)

Enzyme co-localization with glyceraldehyde-3-P dehydrogenase in pea leaf chloroplasts. Louise Anderson^*,1, Andrew Carol¹, ¹ Biological Sciences, University of Illinois-Chicago, Chicago, IL, USA

ABSTRACT- Substrate channeling between the enzymes of the reductive pentose phosphate pathway has the potential to enhance the rate of photosynthetic CO2 fixation. We have used nearest neighbor analysis of immunolabeling on thin sections (Anderson et al., J. Structural Biol. 143:95-106, 2003) to demonstrate that both the A and B subunits of the chloroplastic NADP-linked glyceraldehyde-3-P dehydrogenase are co-localized with P-glycerate kinase, triose-P isomerase, aldolase, and transketolase, in situ. These enzymes might, therefore, exist as complexes capable of channeling intermediates from one to the other, in vivo. The dehydrogenase is also co-localized with phosphoribulokinase and with Rubisco. Supported by a grant from US NSF.

KEY WORDS: GAPDH, substrate channeling, PGK, aldolase