Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: KEGG:D02011 (FAD)
 5,530 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mycobacterium tuberculosis H37Rv, the slow-growing human pathogenic strain of tubercle bacilli and Mycobacterium smegmatis and Mycobacterium phlei, the fast-growing saprophytes, have shown variations regarding the type of dehydrogenase that initiates malate oxidation in the respiratory chain. M. tuberculosis H37Rv is characterized by having a malate oxidase system (designated MALNAD pathway) in which malate oxidation is mediated by the NAD+-dependent malate dehydrogenase (EC 1.1.1.37) but not by FAD-dependent malate-vitamin K reductase. M. smegmatis possesses a different malate oxidase system (designated MALFAD pathway) in which malate oxidation is exclusively carried out by the FAD-dependent malate-vitamin K reductase because NAD+-dependent malate dehydrogenase is absent in this organism. M. phlei has a mixed system of malate oxidase (designated MALNAD+FAD pathways) in which both the NAD+-and FAD-dependent dehydrogenases take part. In all the three systems, the rest of the electron transport chain is common.
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PMID:Variations in the pathways of malate oxidation and phosphorylation in different species of Mycobacteria. 23 47

The distribution of dye-linked L-malate dehydrogenase (L-malate: acceptor oxidoreductase, EC 1.1.99.16) was investigated in many thermophilic bacteria. The enzyme occurred widely in thermophilic spore-forming bacteria like bacilli and thermoactinomycetes. The enzyme was purified to homogeneity from a thermophile, Bacillus sp. DSM 465, with a 2.7% overall recovery by DEAE-Toyopearl column chromatography, Sephacryl S-400 column chromatography and preparative slab PAGE. The enzyme had a molecular mass of about 660 kDa and consisted of about ten subunits all with a molecular mass of 66 kDa. The enzyme retained its full activity upon heating at 55 degrees C for at least 60 min and with incubation at pH 5.0-10.0, 55 degrees C, for 10 min. The enzyme exclusively catalyzed L-malate dehydrogenation in the presence of an electron acceptor such as 2,6-dichloroindophenol. The Michaelis constants for L-malate and 2,6-dichloroindophenol were determined to be 1.67 mM and 0.050 mM, respectively. FAD was identified as a prosthetic group of the enzyme by HPLC.
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PMID:Dye-linked L-malate dehydrogenase from thermophilic Bacillus species DSM 465. Purification and characterization. 850 4

In addition to a cytoplasmic, NAD-dependent malate dehydrogenase (EC 1.1.1.37), Corynebacterium glutamicum possesses a highly active membrane-associated malate dehydrogenase (acceptor) (EC 1.1.99.16). This enzyme also takes part in the citric acid cycle. It oxidizes L-malate to oxaloacetate and donates electrons to ubiquinone-1 and other artificial acceptors or, via the electron transfer chain, to oxygen. NAD is not an acceptor and the natural direct acceptor for the enzyme is most likely a quinone. The enzyme is therefore called malate:quinone oxidoreductase, abbreviated to Mqo. Mqo is a peripheral membrane protein and can be released from the membrane by addition of chelators. The solubilized form was partially purified and characterized biochemically. FAD is probably a tightly but non-covalently bound prosthetic group, and the enzyme is activated by lipids. A C. glutamicum mutant completely lacking Mqo activity was isolated. It grows poorly on several substrates tested. The mutant possesses normal levels of cytoplasmic NAD-dependent malate dehydrogenase. A plasmid containing the gene from C. glutamicum coding for Mqo was isolated by complementation of the Mqo-negative phenotype. It leads to overexpression of Mqo activity in the mutant. The nucleotide sequence of the mqo gene was determined and is the first sequence known for this enzyme. The derived protein sequence is similar to hypothetical proteins from Escherichia coli, Klebsiella pneumoniae, and Mycobacterium tuberculosis.
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PMID:Biochemical and genetic characterization of the membrane-associated malate dehydrogenase (acceptor) from Corynebacterium glutamicum. 966 Jan 97

Membrane-bound NAD(P)-independent malate dehydrogenase (EC 1.1.99.16) was purified to homogeneity from the membrane of thermotolerant Acetobacter sp. SKU 14, an isolate from Thailand. The enzyme was solubilized from the membrane fraction of glycerol-grown cells with 1% Triton X-100 in the presence of 0.1 M KCl, and purified to homogeneity through steps of column chromatographies on DEAE-Sephadex A-50 and DEAE-Toyopearl in the presence of 0.1% Triton X-100. The purified enzyme showed a single protein band in both native-PAGE and SDS-PAGE. The enzyme was a homodimer with a molecular mass of 60 kDa subunit and had noncovalently bound FAD as the cofactor. The enzyme was stable over pH 5 and had its maximum activity at pH 11.0 when ferricyanide was used as an electron acceptor. The enzyme activity was elevated by the addition of ammonium ions. The substrate specificity was very strict to only L-malate, of which the apparent Km was 10 mM and over 20 compounds involving D-malate were not oxidized by the enzyme.
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PMID:Purification and characterization of membrane-bound malate dehydrogenase from Acetobacter sp. SKU 14. 1199 2