Specific Arabidopsis thaliana malic enzyme isoforms can provide anaplerotic pyruvate carboxylation function in Saccharomyces cerevisiae

Specific Arabidopsis thaliana malic enzyme isoforms can provide anaplerotic pyruvate carboxylation function in Saccharomyces cerevisiae

Badia, Mariana Beatriz (Universidad Nacional de Rosario)
Mans, R. (TU Delft BT/Industriele Microbiologie)
Lis, A.V. (TU Delft BT/Industriele Microbiologie; Saarland University)
Tronconi, Marcos Ariel (Universidad Nacional de Rosario)
Arias, Cintia Lucía (Universidad Nacional de Rosario)
Maurino, Verónica Graciela (Universität Düsseldorf)
Andreo, Carlos Santiago (Universidad Nacional de Rosario)
Drincovich, María Fabiana (Universidad Nacional de Rosario)
van Maris, A.J.A. (TU Delft BT/Industriele Microbiologie; KTH Royal Institute of Technology)
Gerrard Wheeler, Mariel Claudia (Universidad Nacional de Rosario)

2017

NAD(P)-malic enzyme (NAD(P)-ME) catalyzes the reversible oxidative decarboxylation of malate to pyruvate, CO₂, and NAD(P)H and is present as a multigene family in Arabidopsis thaliana. The carboxylation reaction catalyzed by purified recombinant Arabidopsis NADP-ME proteins is faster than those reported for other animal or plant isoforms. In contrast, no carboxylation activity could be detected in vitro for the NAD-dependent counterparts. In order to further investigate their putative carboxylating role in vivo, Arabidopsis NAD(P)-ME isoforms, as well as the NADP-ME2del2 (with a decreased ability to carboxylate pyruvate) and NADP-ME2R115A (lacking fumarate activation) versions, were functionally expressed in the cytosol of pyruvate carboxylase-negative (Pyc⁻) Saccharomyces cerevisiae strains. The heterologous expression of NADP-ME1, NADP-ME2 (and its mutant proteins), and NADP-ME3 restored the growth of Pyc⁻ S. cerevisiae on glucose, and this capacity was dependent on the availability of CO₂. On the other hand, NADP-ME4, NAD-ME1, and NAD-ME2 could not rescue the Pyc⁻ strains from C₄ auxotrophy. NADP-ME carboxylation activity could be measured in leaf crude extracts of knockout and overexpressing Arabidopsis lines with modified levels of NADP-ME, where this activity was correlated with the amount of NADP-ME2 transcript. These results indicate that specific A. thaliana NADP-ME isoforms are able to play an anaplerotic role in vivo and provide a basis for the study on the carboxylating activity of NADP-ME, which may contribute to the synthesis of C₄ compounds and redox shuttling in plant cells.

anaplerotic role
C4 organic acids
malate synthesis
plant metabolism
Saccharomyces cerevisiae

http://resolver.tudelft.nl/uuid:739f55d3-6ace-4d2b-97d5-457a94043aab

https://doi.org/10.1111/febs.14013

2019-03-22

1742-464X

The FEBS Journal, 284 (4), 654-665

Accepted Author Manuscript Title Manuscript differs from the publishers version

Institutional Repository

journal article

© 2017 Mariana Beatriz Badia, R. Mans, A.V. Lis, Marcos Ariel Tronconi, Cintia Lucía Arias, Verónica Graciela Maurino, Carlos Santiago Andreo, María Fabiana Drincovich, A.J.A. van Maris, Mariel Claudia Gerrard Wheeler