Malate dehydrogenase (decarboxylating)

Thus, the two substrates of this enzyme are (S)-malate and NAD⁺, whereas its three products are pyruvate, CO₂, and NADH. Malate is oxidized to pyruvate and CO₂, and NAD⁺ is reduced to NADH.

This enzyme belongs to the family of oxidoreductases, to be specific, those acting on the CH-OH group of donor with NAD⁺ or NADP⁺ as acceptor. The systematic name of this enzyme class is (S)-malate:NAD⁺ oxidoreductase (decarboxylating). This enzyme participates in pyruvate metabolism and carbon fixation. NAD-malic enzyme is one of three decarboxylation enzymes used in the inorganic carbon concentrating mechanisms of C₄ and CAM plants. The others are NADP-malic enzyme and PEP carboxykinase.^[1]^[2]

Structural studies

As of late 2007, 7 structures have been solved for this class of enzymes, with PDB accession codes 1DO8, 1EFK, 1EFL, 1PJ2, 1PJ3, 1PJ4, and 1QR6.

References

↑ Kanai R, Edwards, GE (1999). "3. The Biochemistry of C₄ Photosynthesis". In Sage RF, Monson RK. C₄ Plant Biology. pp. 43–87. ISBN 0126144400.
↑ Christopher JT, Holtum JAM (1996). "Patterns of carbon partitioning in leaves of Crassulacean acid metabolism species during deacidification". Plant Physiol. 112 (1): 393–399. doi:10.1104/pp.112.1.393. PMC: 157961. PMID 12226397.

Saz HJ and Hubbard JA (1957). "The oxidative decarboxylation of malate by Ascaris lumbricoides". J. Biol. Chem. 225 (2): 921–933. PMID 13416294.

Oxidoreductases: alcohol oxidoreductases (EC 1.1)

1.1.1: NAD/NADP acceptor	3-hydroxyacyl-CoA dehydrogenase 3-hydroxybutyryl-CoA dehydrogenase Alcohol dehydrogenase Aldo-keto reductase 1A1 1B1 1B10 1C1 1C3 1C4 7A2 Aldose reductase Beta-Ketoacyl ACP reductase Carbohydrate dehydrogenases Carnitine dehydrogenase D-malate dehydrogenase (decarboxylating) DXP reductoisomerase Glucose-6-phosphate dehydrogenase Glycerol-3-phosphate dehydrogenase HMG-CoA reductase IMP dehydrogenase Isocitrate dehydrogenase Lactate dehydrogenase L-threonine dehydrogenase L-xylulose reductase Malate dehydrogenase Malate dehydrogenase (decarboxylating) Malate dehydrogenase (NADP+) Malate dehydrogenase (oxaloacetate-decarboxylating) Malate dehydrogenase (oxaloacetate-decarboxylating) (NADP+) Phosphogluconate dehydrogenase Sorbitol dehydrogenase Hydroxysteroid dehydrogenase: 3 Beta 3-beta-HSD NSDHL 11 Beta HSD11B1 HSD11B2 17 Beta

1.1.2: cytochrome acceptor	D-lactate dehydrogenase (cytochrome) D-lactate dehydrogenase (cytochrome c-553) Mannitol dehydrogenase (cytochrome)

1.1.3: oxygen acceptor	Glucose oxidase L-gulonolactone oxidase Xanthine oxidase

1.1.4: disulfide as acceptor	Vitamin K epoxide reductase Vitamin-K-epoxide reductase (warfarin-insensitive)

1.1.5: quinone/similar acceptor	Malate dehydrogenase (quinone) Quinoprotein glucose dehydrogenase

1.1.99: other acceptors	Choline dehydrogenase L2HGDH

Enzymes

Activity	Active site Binding site Catalytic triad Oxyanion hole Enzyme promiscuity Catalytically perfect enzyme Coenzyme Cofactor Enzyme catalysis Enzyme kinetics Lineweaver–Burk plot Michaelis–Menten kinetics

Regulation	Allosteric regulation Cooperativity Enzyme inhibitor

Classification	EC number Enzyme superfamily Enzyme family List of enzymes

Types	EC1 Oxidoreductases(list) EC2 Transferases(list) EC3 Hydrolases(list) EC4 Lyases(list) EC5 Isomerases(list) EC6 Ligases(list)

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