malic enzyme activity
Definition
Target type: molecularfunction
Catalysis of the oxidative decarboxylation of malate with the concomitant production of pyruvate. [ISBN:0198506732]
Malic enzyme activity is a crucial metabolic process catalyzed by the enzyme malic enzyme. This enzyme is involved in the conversion of malate to pyruvate, a key step in various metabolic pathways, including:
- **Carbohydrate metabolism:** Malic enzyme plays a role in gluconeogenesis, the synthesis of glucose from non-carbohydrate precursors. It provides a source of pyruvate, a vital substrate for glucose production.
- **Energy metabolism:** In some organisms, malic enzyme participates in the oxidative decarboxylation of malate, generating NADPH, a crucial reducing agent for various metabolic reactions. This process contributes to the production of ATP, the primary energy currency of cells.
- **Photosynthesis:** In plants, malic enzyme is involved in the C4 carbon fixation pathway, a process that enhances photosynthetic efficiency in hot and dry climates.
- **Fatty acid synthesis:** In some organisms, malic enzyme contributes to the synthesis of fatty acids by providing NADPH for the process.
Malic enzyme activity is highly regulated and influenced by various factors, including:
- **Substrate availability:** The availability of malate as a substrate determines the enzyme's activity.
- **Redox state:** The enzyme's activity can be modulated by the cellular redox state, which affects the availability of NAD+ and NADPH.
- **Hormonal regulation:** Hormones such as insulin and glucagon can influence the expression and activity of malic enzyme.
The detailed molecular mechanism of malic enzyme activity involves the following steps:
1. **Binding of malate:** The enzyme binds malate to its active site.
2. **Oxidation of malate:** The enzyme utilizes NAD+ as an electron acceptor to oxidize malate to oxaloacetate.
3. **Decarboxylation:** The enzyme catalyzes the decarboxylation of oxaloacetate, releasing carbon dioxide (CO2) and forming pyruvate.
4. **Reduction of NAD+:** The enzyme reduces NAD+ to NADPH, using the electrons from the oxidation of malate.
The specific reaction catalyzed by malic enzyme can be summarized as follows:
Malate + NAD+ → Pyruvate + CO2 + NADPH
Malic enzyme activity is a complex process with significant implications for various metabolic pathways. Its precise role and regulation vary depending on the organism and the specific metabolic context.'
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Proteins (2)
| Protein | Definition | Taxonomy |
|---|---|---|
| NADP-dependent malic enzyme, mitochondrial | An NADP-dependent malic enzyme, mitochondrial that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q16798] | Homo sapiens (human) |
| Malate dehydrogenase, cytoplasmic | A malate dehydrogenase, cytoplasmic that is encoded in the genome of human. [PRO:DNx, UniProtKB:P40925] | Homo sapiens (human) |
Compounds (14)
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| succinic acid | succinic acid : An alpha,omega-dicarboxylic acid resulting from the formal oxidation of each of the terminal methyl groups of butane to the corresponding carboxy group. It is an intermediate metabolite in the citric acid cycle. Succinic Acid: A water-soluble, colorless crystal with an acid taste that is used as a chemical intermediate, in medicine, the manufacture of lacquers, and to make perfume esters. It is also used in foods as a sequestrant, buffer, and a neutralizing agent. (Hawley's Condensed Chemical Dictionary, 12th ed, p1099; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1851) | alpha,omega-dicarboxylic acid; C4-dicarboxylic acid | anti-ulcer drug; fundamental metabolite; micronutrient; nutraceutical; radiation protective agent |
| benzyl benzoate | benzyl benzoate : A benzoate ester obtained by the formal condensation of benzoic acid with benzyl alcohol. It has been isolated from the plant species of the genus Polyalthia. benzyl benzoate: structure; acarosan, a moist powder composed of wetted cellulose and benzyl benzoate, is used on carpets as an acaricide | benzoate ester; benzyl ester | acaricide; plant metabolite; scabicide |
| clotrimazole | conazole antifungal drug; imidazole antifungal drug; imidazoles; monochlorobenzenes | antiinfective agent; environmental contaminant; xenobiotic | |
| econazole | 1-{2-(4-chlorobenzyloxy)-2-(2,4-dichlorophenyl)ethyl}imidazole : A member of the class of imidazoles that is 1-(2,4-dichlorophenyl)-2-(imidazol-1-yl)ethanol in which the hydroxyl hydrogen is replaced by a 4-chlorobenzyl group. econazole : A racemate composed of equimolar amounts of (R)- and (S)-econazole. Used (as its nitrate salt) to treat skin infections such as athlete's foot, jock itch, ringworm and other fungal skin infections. Econazole: An imidazole derivative that is commonly used as a topical antifungal agent. | dichlorobenzene; ether; imidazoles; monochlorobenzenes | |
| fluconazole | fluconazole : A member of the class of triazoles that is propan-2-ol substituted at position 1 and 3 by 1H-1,2,4-triazol-1-yl groups and at position 2 by a 2,4-difluorophenyl group. It is an antifungal drug used for the treatment of mucosal candidiasis and for systemic infections including systemic candidiasis, coccidioidomycosis, and cryptococcosis. Fluconazole: Triazole antifungal agent that is used to treat oropharyngeal CANDIDIASIS and cryptococcal MENINGITIS in AIDS. | conazole antifungal drug; difluorobenzene; tertiary alcohol; triazole antifungal drug | environmental contaminant; P450 inhibitor; xenobiotic |
| glyburide | glyburide : An N-sulfonylurea that is acetohexamide in which the acetyl group is replaced by a 2-(5-chloro-2-methoxybenzamido)ethyl group. Glyburide: An antidiabetic sulfonylurea derivative with actions like those of chlorpropamide | monochlorobenzenes; N-sulfonylurea | anti-arrhythmia drug; EC 2.7.1.33 (pantothenate kinase) inhibitor; EC 3.6.3.49 (channel-conductance-controlling ATPase) inhibitor; hypoglycemic agent |
| ketoconazole | 1-acetyl-4-(4-{[2-(2,4-dichlorophenyl)-2-(1H-imidazol-1-ylmethyl)-1,3-dioxolan-4-yl]methoxy}phenyl)piperazine : A dioxolane that is 1,3-dioxolane which is substituted at positions 2, 2, and 4 by imidazol-1-ylmethyl, 2,4-dichlorophenyl, and [para-(4-acetylpiperazin-1-yl)phenoxy]methyl groups, respectively. | dichlorobenzene; dioxolane; ether; imidazoles; N-acylpiperazine; N-arylpiperazine | |
| mefenamic acid | mefenamic acid : An aminobenzoic acid that is anthranilic acid in which one of the hydrogens attached to the nitrogen is replaced by a 2,3-dimethylphenyl group. Although classed as a non-steroidal anti-inflammatory drug, its anti-inflammatory properties are considered to be minor. It is used to relieve mild to moderate pain, including headaches, dental pain, osteoarthritis and rheumatoid arthritis. Mefenamic Acid: A non-steroidal anti-inflammatory agent with analgesic, anti-inflammatory, and antipyretic properties. It is an inhibitor of cyclooxygenase. | aminobenzoic acid; secondary amino compound | analgesic; antipyretic; antirheumatic drug; EC 1.14.99.1 (prostaglandin-endoperoxide synthase) inhibitor; environmental contaminant; non-steroidal anti-inflammatory drug; xenobiotic |
| miconazole | 1-[2-(2,4-dichlorobenzyloxy)-2-(2,4-dichlorophenyl)ethyl]imidazole : A member of the class of imidazoles that is 1-(2,4-dichlorophenyl)-2-(imidazol-1-yl)ethanol in which the hydroxyl hydrogen is replaced by a 2,4-dichlorobenzyl group. miconazole : A racemate composed of equimolar amounts of (R)- and (S)-miconazole. Used (as its nitrate salt) to treat skin infections such as athlete's foot, jock itch, ringworm and other fungal skin infections. It inhibits the synthesis of ergosterol, a critical component of fungal cell membranes. Miconazole: An imidazole antifungal agent that is used topically and by intravenous infusion. | dichlorobenzene; ether; imidazoles | |
| nicardipine | 2-[benzyl(methyl)amino]ethyl methyl 2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate : A dihydropyridine that is 1,4-dihydropyridine substituted by a methyl, {2-[benzyl(methyl)amino]ethoxy}carbonyl, 3-nitrophenyl, methoxycarbonyl and methyl groups at positions 2, 3, 4, 5 and 6, respectively. nicardipine : A racemate comprising equimolar amounts of (R)- and (S)-nicardipine. It is a calcium channel blocker which is used to treat hypertension. Nicardipine: A potent calcium channel blockader with marked vasodilator action. It has antihypertensive properties and is effective in the treatment of angina and coronary spasms without showing cardiodepressant effects. It has also been used in the treatment of asthma and enhances the action of specific antineoplastic agents. | benzenes; C-nitro compound; diester; dihydropyridine; methyl ester; tertiary amino compound | |
| oxaprozin | oxaprozin : A monocarboxylic acid that is a propionic acid derivative having a 4,5-diphenyl-1,3-oxazol-2-yl substituent at position 3. It is non-steroidal anti-inflammatory drug commonly used to relieve the pain and inflammatory responses associated with osteoarthritis and rheumatoid arthritis. Oxaprozin: An oxazole-propionic acid derivative, cyclooxygenase inhibitor, and non-steroidal anti-inflammatory drug that is used in the treatment of pain and inflammation associated with of OSTEOARTHRITIS; RHEUMATOID ARTHRITIS; and ARTHRITIS, JUVENILE. | 1,3-oxazoles; monocarboxylic acid | analgesic; non-steroidal anti-inflammatory drug |
| sulconazole | 1-{2-[(4-chlorobenzyl)sulfanyl]-2-(2,4-dichlorophenyl)ethyl}-1H-imidazole : A member of the class of imidazoles that is 1-ethyl-1H-imidazole in which one of the hydrogens of the methyl group is replaced by a (4-chlorobenzyl)sulfanediyl group while a second is replaced by a 2,4-dichlorophenyl group. sulconazole : A racemate comprising equimolar amounts of (R)- and (S)-sulconazole. An antifungal agent with activity against Candida species, it is used (generally as the nitrate salt) for the topical treatment of fungal skin infections. sulconazole: RN given refers to cpd with unspecified isomeric designation; structure given in first source | dichlorobenzene; imidazoles; monochlorobenzenes; organic sulfide | |
| delavirdine | delavirdine : The amide resulting from the formal condensation of 5-[(methylsulfonyl)amino]-1H-indole-2-carboxylic acid and 4-amino group of 1-[3-(isopropylamino)pyridin-2-yl]piperazine, delavirdine is a non-nucleoside reverse transcriptase inhibitor with activity specific for HIV-1. Viral resistance emerges rapidly when delavirdine is used alone, so it is therefore used (as the methanesulfonic acid salt) with other antiretrovirals for combination therapy of HIV infection. Delavirdine: A potent, non-nucleoside reverse transcriptase inhibitor with activity specific for HIV-1. | aminopyridine; indolecarboxamide; N-acylpiperazine; sulfonamide | antiviral drug; HIV-1 reverse transcriptase inhibitor |
| fumaric acid | fumaric acid : A butenedioic acid in which the C=C double bond has E geometry. It is an intermediate metabolite in the citric acid cycle. fumaric acid: see also record for ferrous fumarate; use FUMARATES for general fumaric acid esters | butenedioic acid | food acidity regulator; fundamental metabolite; geroprotector |