Key features and details
- Assay type: Enzyme activity
- Detection method: Colorimetric
- Platform: Microplate reader
- Sample type: Cell culture extracts, Tissue Extracts
- Sensitivity: 0.78 µg/ml
Product nameMalate Dehydrogenase 2 (MDH2) Activity Assay
See all MDH2 kits
Intra-assay Sample n Mean SD CV% 1 3 4.1% Inter-assay Sample n Mean SD CV% 1 3 13.9%
Sample typeCell culture extracts, Tissue Extracts
Assay typeEnzyme activity
Range0.78 µg/ml - 200 µg/ml
Species reactivityReacts with: Mouse, Rat, Human
Malate Dehydrogenase 2 (MDH2) Activity Assay (ab119693) is used to determine mitochondrial malate dehydrogenase activity (MDH2) in a sample. The enzyme is captured within the wells of the microplate and activity is determined by following the production of NADH in the following MDH2 catalyzed reaction: malate + NAD → oxaloacetic acid + NADH (↑ Absorbance at 450 nm). The generation of NADH is coupled to the 1:1 reduction of a reporter dye to yield a colored (yellow) reaction product whose concentration can be monitored by measuring the increase in absorbance at 450 nm. In each well, ab119693 immunocaptures only native MDH2 from the chosen sample; this removes all other enzymes, including MDH1 in cytosol.
This product allows researchers to focus on TCA cycle, studying isotype-specific malate dehydrogenase (MDH2) activity assay without the necessity of isolating mitochondria.
Mitochondrial malate dehydrogenase (MDH2, P40926) is a 35.5 kDa enzyme that catalyzes the conversion of malate into oxaloacetate (using NAD+) and vice versa. (EC 18.104.22.168) Several isozymes of malate dehydrogenase exist, depending on where they are localized in the cell and their specific dependence on NAD+ or NADP+ (only in chloroplasts). There are two main isoforms in eukaryotic cells. One is found in the mitochondrial matrix (MDH2), participating as a key enzyme in the citric acid cycle that catalyzes the oxidation of malate. The other is found in the cytoplasm (MDH1), assisting the malate-aspartate shuttle with exchanging reducing equivalents so that malate can pass through the mitochondrial membrane to be transformed into oxaloacetate for further cellular processes. Because malate dehydrogenase is closely tied to the citric acid cycle, regulation is highly dependent on TCA products. High malate concentrations stimulate MDH activity, and, in a converse manner, high oxaloacetate concentrations inhibit the enzyme. Enzyme activity is enhanced by acetylation.
Storage: All components are shipped cold. Reagent dye, coupler, malate and NAD+ are shipped lyophilized. Before use rehydrate by adding 0.25 mL pure H2O to each tube and vortex each tube thoroughly to dissolve. After hydration unused amounts of these four materials should be stored at -80°C for 6 months. Store all other components at 4°C. This kit is stable for 6 months from receipt.
Storage instructionsStore at +4°C. Please refer to protocols.
Components 1 x 96 tests 100X Coupler 1 unit 100X NAD+ 1 unit 100X Reagent Dye 1 unit 100X Sodium Malate 1 unit 10X Blocking Buffer 1 x 8ml 20X Buffer 1 x 20ml Base Buffer 1 x 24ml Extraction Buffer (ab260490) 1 x 15ml MDH2 Microplate 1 unit
Sequence similaritiesBelongs to the LDH/MDH superfamily. MDH type 1 family.
modificationsAcetylation is enhanced by up to 67% after treatment either with trichostin A (TSA) or with nicotinamide (NAM) with the appearance of tri-and tetraacetylations. Glucose also increases acetylation by about 60%.
Cellular localizationMitochondrion matrix.
- Information by UniProt
- M MDH
- Malate dehydrogenase
- Malate dehydrogenase 2, NAD (mitochondrial)
- Rat liver tissue lysate - mitochondrial extract (ab110346)
- Rat heart tissue lysate - mitochondrial extract (ab110347)
- Rat brain tissue lysate - mitochondrial extract (ab110348)
- Mouse liver tissue lysate - mitochondrial extract (ab110349)
- Mouse heart tissue lysate - mitochondrial extract (ab110350)
- Mouse brain tissue lysate - mitochondrial extract (ab110351)
Figures 7. The isoform specificity of the malate activity measured by this kit is confirmed by measuring the MDH activity from different cell fractions. Activity was only detected from the mitochondrial fraction (MDH2), not the cytosol fraction (MDH1).
Figure 4. MDH2 antibody showing reactivity in a mitochondrial intracellular pattern with immunofluorescence microscopy.
Figure 2. MDH2 activity measurements of serially diluted human liver homogenate, rat heart homogenate, and mouse liver homogenate.
Figure 1. MDH2 activity measurements of serially diluted cultured HepG2 cell extracts.
ab119693 has been referenced in 4 publications.
- Calmels C et al. Application of a genome-scale model in tandem with enzyme assays for identification of metabolic signatures of high and low CHO cell producers. Metab Eng Commun 9:e00097 (2019). PubMed: 31720213
- Lee WT et al. Mitochondrial DNA haplotypes induce differential patterns of DNA methylation that result in differential chromosomal gene expression patterns. Cell Death Discov 3:17062 (2017). PubMed: 28900542
- Ait-El-Mkadem S et al. Mutations in MDH2, Encoding a Krebs Cycle Enzyme, Cause Early-Onset Severe Encephalopathy. Am J Hum Genet 100:151-159 (2017). PubMed: 27989324
- Kim EY et al. Acceleration of adipogenic differentiation via acetylation of malate dehydrogenase 2. Biochem Biophys Res Commun 441:77-82 (2013). PubMed: 24134846