Publications

• Retinal oxidase is identical to aldehyde oxidase.

  Tomita S., Tsujita M., Ichikawa Y.

  Retinal oxidase (EC 1.2.3.11) and aldehyde oxidase (EC 1.2.3.1) were compared with respect to their enzymatic and physiochemical properties. It was found that the molecular weights, subunits, optical spectra, chemical and immunological properties, cellular localization and substrate specificities ... >> More

  Retinal oxidase (EC 1.2.3.11) and aldehyde oxidase (EC 1.2.3.1) were compared with respect to their enzymatic and physiochemical properties. It was found that the molecular weights, subunits, optical spectra, chemical and immunological properties, cellular localization and substrate specificities of the two oxidases are identical on almost all points. The physiological function of aldehyde oxidase appears to be the synthesis of retinoic acid from retinal. << Less

  FEBS Lett 336:272-274(1993) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.

• Purification and characterization of hepatic aldehyde oxidase in male and female mice.

  Yoshihara S., Tatsumi K.

  To examine whether the hepatic aldehyde oxidases of male and female mice, which exhibit sex-related differences in benzaldehyde oxidation, are qualitatively different, we purified the enzymes from untreated male and female ddy mice and testosterone-pretreated female mice by sequential chromatograp ... >> More

  To examine whether the hepatic aldehyde oxidases of male and female mice, which exhibit sex-related differences in benzaldehyde oxidation, are qualitatively different, we purified the enzymes from untreated male and female ddy mice and testosterone-pretreated female mice by sequential chromatography of benzamidine-Sepharose 6B and DEAE-5PW columns and characterized the enzymes. Purified enzymes from untreated male and female mice and from testosterone-treated females gave a single protein band at M(r) 265K and M(r) 138K on native and SDS-polyacrylamide gradient gel electrophoresis, respectively. The susceptibilities of the enzymes from both sexes to inhibitors such as menadione, norharman, quinacrine, estradiol, and SKF 525-A were also indistinguishable. However, the K(m) values for benzaldehyde, p-dimethylaminocinnamaldehyde, and 2-hydroxypyrimidine were two-to fourfold higher in the untreated female enzyme than in the untreated male enzyme, while the testosterone-induced female enzyme showed K(m) values similar to those of the male enzyme. These results indicate that the hepatic aldehyde oxidases of the sexes are quite similar with respect to molecular size and susceptibility to inhibitors, but their kinetic properties are somewhat different, suggesting the existence of microheterogeneity in sex differences. It also suggests that treatment of female mice with testosterone might induce the male-type enzyme. << Less

  Arch Biochem Biophys 338:29-34(1997) [PubMed] [EuropePMC]

• In vitro oxidation of famciclovir and 6-deoxypenciclovir by aldehyde oxidase from human, guinea pig, rabbit, and rat liver.

  Rashidi M.R., Smith J.A., Clarke S.E., Beedham C.

  Famciclovir, a 9-substituted guanine derivative, is a new antiviral agent which undergoes rapid hydrolysis and oxidation in man to yield the active antiherpes agent, penciclovir. Studies with human liver cytosol have indicated that the oxidation of the penultimate metabolite, 6-deoxypenciclovir, t ... >> More

  Famciclovir, a 9-substituted guanine derivative, is a new antiviral agent which undergoes rapid hydrolysis and oxidation in man to yield the active antiherpes agent, penciclovir. Studies with human liver cytosol have indicated that the oxidation of the penultimate metabolite, 6-deoxypenciclovir, to penciclovir is catalyzed by the molybdenum hydroxylase, aldehyde oxidase. In the present study the oxidation of famciclovir and 6-deoxypenciclovir with partially purified molybdenum hydroxylases from human, guinea pig, rabbit, and rat livers and bovine milk xanthine oxidase has been investigated. Famciclovir and 6-deoxypenciclovir were oxidized predominantly to 6-oxo-famciclovir and penciclovir, respectively, by human, guinea pig, and rat liver aldehyde oxidase. Small amounts of 8-oxo and 6,8-dioxo-metabolites were also formed from each substrate. Famciclovir and 6-deoxypenciclovir were good substrates for rabbit liver aldehyde oxidase but, in each case, two major metabolites were formed. 6-Deoxypenciclovir was converted to penciclovir and 8-oxo-6-deoxypenciclovir in approximately equal quantities; famciclovir was oxidized to 6-oxo-famciclovir and a second metabolite which, on the basis of chromatographic and UV spectral data, was thought to be 8-oxo-famciclovir. Two groups of Sprague Dawley rats were identified; those containing hepatic aldehyde oxidase and xanthine oxidase and those with only xanthine oxidase. These have been designated AO-active and AO-inactive rats, respectively. Famciclovir was not oxidized by enzyme from AO-inactive rats or bovine milk xanthine oxidase although 6-deoxypenciclovir was slowly converted to penciclovir by rat liver or milk xanthine oxidase. Inhibitor studies showed in human, guinea pig, and rabbit liver that xanthine oxidase did not contribute to the oxidation of famciclovir and 6-deoxypenciclovir; thus it is proposed that drug activation in vivo would be catalyzed solely by aldehyde oxidase. << Less

  Drug Metab. Dispos. 25:805-813(1997) [PubMed] [EuropePMC]

• Molecular cloning of retinal oxidase/aldehyde oxidase cDNAs from rabbit and mouse livers and functional expression of recombinant mouse retinal oxidase cDNA in Escherichia coli.

  Huang D.-Y., Furukawa A., Ichikawa Y.

  Retinal oxidase (EC 1.2.3.11) is a molybdenum-containing flavoenzyme with high enzymatic activity as to retinoic acid synthesis. In this study, we provide direct evidence that retinal oxidase is identical to aldehyde oxidase (EC 1.2.3.1) by cDNA cloning. Retinal oxidase and aldehyde oxidase, purif ... >> More

  Retinal oxidase (EC 1.2.3.11) is a molybdenum-containing flavoenzyme with high enzymatic activity as to retinoic acid synthesis. In this study, we provide direct evidence that retinal oxidase is identical to aldehyde oxidase (EC 1.2.3.1) by cDNA cloning. Retinal oxidase and aldehyde oxidase, purified from rabbit liver cytosol using the original methods, showed completely identical HPLC patterns and amino acid sequences for three corresponding polypeptides (103 amino residues). The primary structural information obtained from the cleaved polypeptides permitted molecular cloning of the full-length cDNA of rabbit liver retinal oxidase (aldehyde oxidase). We also cloned and sequenced the full-length cDNA of mouse retinal oxidase. The cDNAs of rabbit and mouse retinal oxidase have a common sequence approximately 4.6 kb long, comprising 4-kb coding regions. The open reading frames of the cDNAs predict single polypeptides of 1334 and 1333 amino acids; the calculated minimum molecular mass of each is approximately 147,000. Northern blot analysis showed that the rabbit retinal oxidase mRNA was widely expressed in tissues. Finally, we successfully constructed a prokaryotic expression system for mouse retinal oxidase. The purified recombinant retinal oxidase from Escherichia coli showed a typical spectrum of aldehyde oxidases and a lower Km (3.8 microM) for retinal and a higher Vmax (807 nmol/min/mg protein) for retinoic acid synthesis than those of rabbit retinal oxidase (8 microM and 496 nmol/min/mg protein). This represents the first eukaryotic molybdenum-containing flavoprotein to be expressed in an active form in a prokaryotic system. << Less

  Arch. Biochem. Biophys. 364:264-272(1999) [PubMed] [EuropePMC]

  This publication is cited by 2 other entries.

• A comparison of the specificities of xanthine oxidase and aldehyde oxidase.

  Krenitsky T.A., Neil S.M., Elion G.B., Hitchings G.H.

  Arch Biochem Biophys 150:585-599(1972) [PubMed] [EuropePMC]

• Purification and characterization of an aldehyde oxidase from Pseudomonas sp. KY 4690.

  Uchida H., Kondo D., Yamashita A., Nagaosa Y., Sakurai T., Fujii Y., Fujishiro K., Aisaka K., Uwajima T.

  An aldehyde oxidase, which oxidizes various aliphatic and aromatic aldehydes using O(2) as an electron acceptor, was purified from the cell-free extracts of Pseudomonas sp. KY 4690, a soil isolate, to an electrophoretically homogeneous state. The purified enzyme had a molecular mass of 132 kDa and ... >> More

  An aldehyde oxidase, which oxidizes various aliphatic and aromatic aldehydes using O(2) as an electron acceptor, was purified from the cell-free extracts of Pseudomonas sp. KY 4690, a soil isolate, to an electrophoretically homogeneous state. The purified enzyme had a molecular mass of 132 kDa and consisted of three non-identical subunits with molecular masses of 88, 39, and 18 kDa. The absorption spectrum of the purified enzyme showed characteristics of an enzyme belonging to the xanthine oxidase family. The enzyme contained 0.89 mol of flavin adenine dinucleotide, 1.0 mol of molybdenum, 3.6 mol of acid-labile sulfur, and 0.90 mol of 5'-CMP per mol of enzyme protein, on the basis of its molecular mass of 145 kDa. Molecular oxygen served as the sole electron acceptor. These results suggest that aldehyde oxidase from Pseudomonas sp. KY 4690 is a new member of the xanthine oxidase family and might contain 1 mol of molybdenum-molybdpterin-cytosine dinucleotide, 1 mol of flavin adenine dinucleotide, and 2 mol of [2Fe-2S] clusters per mol of enzyme protein. The enzyme showed high reaction rates toward various aliphatic and aromatic aldehydes and high thermostability. << Less

  FEMS Microbiol Lett 229:31-36(2003) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.

• Studies on the mechanism of aldehyde oxidase and xanthine oxidase.

  Alfaro J.F., Jones J.P.

  DFT calculations support a concerted mechanism for xanthine oxidase and aldehyde oxidase hydride displacement from the sp(2) carbon of 6-substituted 4-quinazolinones. The variations in transition state structure show that C-O bond formation is nearly complete in the transition state and the transi ... >> More

  DFT calculations support a concerted mechanism for xanthine oxidase and aldehyde oxidase hydride displacement from the sp(2) carbon of 6-substituted 4-quinazolinones. The variations in transition state structure show that C-O bond formation is nearly complete in the transition state and the transition state changes are anti-Hammond with the C-H and C-O bond lengths being more product-like for the faster reactions. The C-O bond length in the transition state is around 90% formed. However, the C-H bond is only about 80% broken. This leads to a very tetrahedral transition state with an O-C-N angle of 109 degrees. Thus, while the mechanism is concerted, the antibonding orbital of the C-H bond that is broken is not directly attacked by the nucleophile and instead hydride displacement occurs after almost complete tetrahedral transition state formation. In support of this the C=N bond is lengthened in the transition state indicating that attack on the electrophilic carbon occurs by addition to the C=N bond with negative charge increasing on the nitrogen. Differences in experimental reaction rates are accurately reproduced by these calculations and tend to support this mechanism. << Less

  J Org Chem 73:9469-9472(2008) [PubMed] [EuropePMC]

• Site directed mutagenesis of amino acid residues at the active site of mouse aldehyde oxidase AOX1.

  Schumann S., Terao M., Garattini E., Saggu M., Lendzian F., Hildebrandt P., Leimkuhler S.

  Mouse aldehyde oxidase (mAOX1) forms a homodimer and belongs to the xanthine oxidase family of molybdoenzymes which are characterized by an essential equatorial sulfur ligand coordinated to the molybdenum atom. In general, mammalian AOs are characterized by broad substrate specificity and an yet o ... >> More

  Mouse aldehyde oxidase (mAOX1) forms a homodimer and belongs to the xanthine oxidase family of molybdoenzymes which are characterized by an essential equatorial sulfur ligand coordinated to the molybdenum atom. In general, mammalian AOs are characterized by broad substrate specificity and an yet obscure physiological function. To define the physiological substrates and the enzymatic characteristics of mAOX1, we established a system for the heterologous expression of the enzyme in Escherichia coli. The recombinant protein showed spectral features and a range of substrate specificity similar to the native protein purified from mouse liver. The EPR data of recombinant mAOX1 were similar to those of AO from rabbit liver, but differed from the homologous xanthine oxidoreductase enzymes. Site-directed mutagenesis of amino acids Val806, Met884 and Glu1265 at the active site resulted in a drastic decrease in the oxidation of aldehydes with no increase in the oxidation of purine substrates. The double mutant V806E/M884R and the single mutant E1265Q were catalytically inactive enzymes regardless of the aldehyde or purine substrates tested. Our results show that only Glu1265 is essential for the catalytic activity by initiating the base-catalyzed mechanism of substrate oxidation. In addition, it is concluded that the substrate specificity of molybdo-flavoenzymes is more complex and not only defined by the three characterized amino acids in the active site. << Less

  PLoS ONE 4:E5348-E5348(2009) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.