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)

We have previously reported the cloning of cDNAs for a flavin-containing mono-oxygenase (FMO) of man, designated FMO1 [Dolphin, Shephard, Povey, Palmer, Ziegler, Ayesh, Smith & Phillips (1991) J. Biol. Chem. 266, 12379-12385], that is the orthologue of pig and rabbit hepatic FMOs. We now describe the isolation and characterization of cDNA clones for a second human FMO, which we have designated FMO2. The polypeptide encoded by the cDNAs is 558 amino acid residues long, has a calculated M(r) of 63337, and contains putative FAD- and NADP-binding sites that align exactly with those described in other mammalian FMOs. Human FMO2 has 51-53% primary sequence identity with human FMO1, rabbit pulmonary FMO and rabbit liver FMO form 2, and thus represents a fourth, distinct, member of the mammalian FMO family. The corresponding mRNA is present in low abundance in adult human liver. Southern blot hybridization with single-exon probes demonstrated that human FMO2 and FMO1 are the products of single genes. The gene encoding FMO2 (designated FMO2) was mapped, by the polymerase chain reaction, to human chromosome 1, the same chromosome on which FMO1 is located.
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PMID:Cloning, primary sequence and chromosomal localization of human FMO2, a new member of the flavin-containing mono-oxygenase family. 141 78

cDNA clones that code for a pig and human flavin-containing monooxygenase (FMO) have been isolated. The full-length sequence of the human cDNAs revealed that they encode a polypeptide of 532 amino acid residues containing putative FAD- and NADP-binding sites. The deduced amino acid sequence has 88 and 86% identity, respectively, with the pig and rabbit "hepatic" forms of FMO, but is only 58% similar to the rabbit "pulmonary" FMO, and thus represents the human ortholog of the "hepatic" form of FMO. However, as this FMO is present in low abundance in human adult liver, the general term "hepatic" for this form of the enzyme is misleading, and thus we propose the name FMO1 to describe this human FMO and its mammalian orthologs. Northern blot analysis demonstrated that human FMO1 mRNA is more abundant in fetal than in adult liver, indicating that in man the enzyme is subject to developmental regulation. Southern blot hybridization of human genomic DNA suggests that the protein is encoded by a single gene, which has been designated FMO1 and mapped to chromosome 1.
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PMID:Cloning, primary sequence, and chromosomal mapping of a human flavin-containing monooxygenase (FMO1). 171 18

A second form of rat liver FMO, FMO-A, was separated and purified by chromatography on Blue Sepharose Fast flow 6. This FMO-A is different from FMO1 by antigenic properties (anti-FMO-A did not cross-react with FMO1, and reciprocally) and by catalytic properties (the Km for trimethylamine was 3.8 microM and 141.4 microM for FMO-A and FMO1, respectively; the Km for imipramine was 536 microM and 17.4 microM for FMO-A and FMO1, respectively). Furthermore, N-terminal amino sequencing revealed differences in the primary structure of these two FMOs although they both contained the highly conserved FAD-binding domain (Gly-X-Gly-X-X-Gly).
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PMID:The flavin-containing monooxygenases in rat liver: evidence for the expression of a second form different from FMO1. 762 16

The flavin-containing monooxygenases (FMO) are a family of enzymes that contain putative FAD- and NADPH-binding domains within the first 200 residues of their N termini. The cDNAs encoding these enzymes contain an area of relatively high identity over the 5' half of the coding region. Rabbit genomic DNA was probed under low stringency conditions, with a mixture of 5' cDNA fragments encoding rabbit FMO1, FMO2, or FMO5. Bands associated specifically with FMO1, FMO2, or FMO5 were resolved by analysis at high stringency with individual probes. Several bands were detected that could not be assigned to FMO1, FMO2, or FMO5. The behavior of the 5' probes at low versus high stringency was used to facilitate the isolation of cDNAs corresponding to the unknown DNA bands. A cDNA library was constructed from rabbit liver mRNA and screened under low stringency hybridization conditions (30 degrees C, 50% formamide, 1 x SSC, 0.1% SDS) with the mixture of 5' FMO1, FMO2, and FMO5 cDNA probes. A total of 157 clones was detected. Of these, 117 clones remained under high stringency hybridization conditions (65 degrees C, 50% formamide, 0.1 x SSC, 0.1% SDS) and were identified as FMO1 (95 clones) or FMO5 (22 clones). Of the 40 remaining clones, 36 were characterized by sequence analysis as encoding FMO3, previously identified at the protein level by Ozols (Ozols, J. (1991) Arch. Biochem. Biophys. 290, 103-115) as a second rabbit liver FMO. Four clones were shown to encode an FMO not previously described for the rabbit, FMO4. No clones encoding FMO2 were isolated from the liver library. Sequence analysis revealed that FMO3 and FMO4 are 56% identical, and analysis of genomic DNA indicated that each is encoded by a single gene. Message distribution was tissue-, species-, and form-specific. The properties of FMO3 cDNA expressed in Escherichia coli were found to be more similar to those of FMO1 than FMO2, but to differ significantly from both. Rabbit genomic DNA was probed under conditions of low stringency with a mixture of 5' cDNA fragments encoding all five FMO forms and produced results consistent with the possibility of one additional FMO.
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PMID:Cloning and sequencing of flavin-containing monooxygenases FMO3 and FMO4 from rabbit and characterization of FMO3. 818 17

The flavin-containing monooxygenases (FMOs) are a family of flavoenzymes and contain one molecule of FAD per monomer. In order to demonstrate where FMO interacts with FAD, four mutants for the rat liver FMO1 protein were expressed in yeast and characterized. All four mutants were immunochemically similar to the unmodified form, although the contents of FAD in all four mutants were much lower than that in the unmodified form. Interestingly, the mutant generated by changing the first glycine of the proposed FAD-binding domain (GxGxxG) to alanine revealed catalytic activities, but was lower than those seen with the unmodified form. The conversion of the first glycine to alanine markedly increased and decreased the Km and Vmax values for imipramine N-oxidation, respectively. The other three mutants (RFMOm2, RFMOm3, and RFMOm4) were catalytically inactive. Our results suggest that three glycines, especially the second and third glycines, in the proposed FAD-binding domain were necessary for FMO to show catalytic activities. Using RFMOm1 and the unmodified form, the effects of n-octylamine on the activity of FMO1 were investigated. The activities of both wild-type and RFMOm1 enzymes for all of the compounds examined were enhanced by n-octylamine. The Km and Vmax values of both RFMOm1 and the unmodified form for imipramine N-oxidation were lowered and raised by n-octylamine, respectively.
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PMID:Determination of FAD-binding domain in flavin-containing monooxygenase 1 (FMO1). 930 99

The sequence of rat FMO3 was obtained by RT-PCR and 5'/3' terminal extension. Complete cDNA was amplified, cloned, and sequenced. The cDNA encodes a protein of 531 amino acids which contains the NADPH- and FAD-binding sites and a hydrophobic carboxyl terminus characteristic of FMOs. This sequence is 81, 81, and 91% identical to sequences of human, rabbit, and mouse FMO3, respectively, and 60% identical to rat FMO1. Rat FMO3 was expressed in Escherichia coli. The recombinant protein and the native protein purified from rat liver microsomes migrated with the same mobility (56 kDa) as determined in sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. Recombinant rat FMO3 showed activities of methimazole S-oxidation, and NADPH oxidation associated with the N- or S-oxidation of trimethylamine and thioacetamide, in good concordance with those reported for human FMO3. When probed with rat FMO3 cDNA (bases 201 to 768), a strong signal corresponding to the 2.3-kb FMO3 transcript was detected in RNA samples from rat liver and kidney while a weak signal was observed with lung RNA samples. In contrast, the probe did not hybridize with any RNA from brain, adipose tissue, or muscle.
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PMID:Cloning, sequencing, tissue distribution, and heterologous expression of rat flavin-containing monooxygenase 3. 1141 82

The expression of flavin-containing monooxygenases (FMOs) in dog liver microsomes was suggested by a high methimazole S-oxidase activity. When the reaction was catalyzed by dog liver microsomes, apparent V(max) and K(m) values were 6.3 nmol/min/mg and 14 microM, respectively. This reaction was highly inhibited (73%) in the presence of imipramine, but it was also weakly affected by trimethylamine, suggesting the involvement of different isoforms. The sequences of dog FMO1 and FMO3 were obtained by reverse transcription-polymerase chain reaction and 5'/3' terminal extension. The cDNAs of dog FMO1 and dog FMO3 encode proteins of 532 amino acids, which contain the NADPH- and FAD-binding sites. The dog FMO1 amino acid sequence is 88, 86, and 89% identical to sequences of human, rabbit, and pig FMO1, respectively. The dog FMO3 amino acid sequence is 83, 84, and 82% identical to sequences of human, rabbit, and rat FMO3, respectively. Dog FMO1 and dog FMO3 exhibited only 56% identities. The FMO1 and FMO3 recombinant proteins and the FMO1 and FMO3 microsomal proteins migrated with the same mobility (56 kDa), as determined in SDS-polyacrylamide gel electrophoresis and immunoblotting. By Western blotting, dog FMO1 and dog FMO3 were detected in microsomes from liver and lung but not in kidney microsomes. By Northern blotting, the probe for FMO1 specifically hybridized a 2.6-kilobase (kb) transcript in liver and lung samples only. The probe for FMO3 hybridized two transcripts of approximately 3 and 4.2 kb in the liver and lung samples.
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PMID:Cloning, sequencing, and tissue-dependent expression of flavin-containing monooxygenase (FMO) 1 and FMO3 in the dog. 1179 79

We cloned a gene from Methylophaga sp. strain SK1. This gene was responsible for producing, the blue pigment, indigo. The complete open reading frame was 1371 bp long, which encodes a protein of 456 amino acids. The molecular mass of the encoded protein was 105 kDa, consisting of homodimer of 54 kDa with an isoelectric point of 5.14. The deduced amino acid sequence from the gene showed approximately 30% identities with flavin-containing monooxygenases (FMOs) of human (FMO1-FMO5), Arabidopsis, and yeast. It contained three characteristic sequence motifs of FMOs: FAD binding domain, FMO-identifying sequence motif, and NADPH binding domain. In addition, the biochemical properties such as substrate specificities and absorption spectra were similar to the eukaryotic FMO families. Thus, we assigned the enzyme to be a bacterial FMO. The recombinant Escherichia coli expressing the bacterial FMO produced up to 160 mg of indigo per liter in the tryptophan medium after 12h cultivation. This suggests that the recombinant strain has a potential to be applied in microbial indigo production.
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PMID:A novel flavin-containing monooxygenase from Methylophaga sp strain SK1 and its indigo synthesis in Escherichia coli. 1282 Nov 31