The molybdo-flavoenzymes are structurally related proteins that require a molybdopterin cofactor and FAD for their catalytic activity. In mammals, four enzymes are known: xanthine oxidoreductase, aldehyde oxidase and two recently described mouse proteins known as aldehyde oxidase homologue 1 and aldehyde oxidase homologue 2. The present review article summarizes current knowledge on the structu...

The activities of aldehyde oxidase and xanthine oxidase were determined in partially purified preparations from livers and kidneys of male and female Dhubb, Uromastyx microlepis, four times daily at equal intervals. The maximum activity of male and female hepatic aldehyde oxidase appeared at 2100 h, whereas the minimum activity was observed at 0300 h, using phthalazine and 3-methylisoquinoline ...

The in vitro metabolism of fenthion and its sulfoxide (fenthion sulfoxide) in sea bream (Pagrus major) and goldfish (Carassius auratus) was investigated and compared with that in rats. Fenthion was oxidized to fenthion sulfoxide and the oxon derivative, but not to its sulfone, in the presence of NADPH by liver microsomes of sea bream, goldfish, and rats. These liver microsomal activities of the...

Iphosphamide [2 (2 chloroethylamino) 3 (2 chloroethyl)tetrahydro-2//-l ,3,2-oxazaphosphorine 2-oxide] is metabolized by mouse liver microsomes in the presence of reduced triphosphopyridine nucleotide and oxygen. When purified aldehyde oxidase is added, the initial metabolites do not appear in quantity; but a single, anionic product is present. After chemical methylation, the mass spectrum of th...

The nicotinamide N-oxide reductase activity of a variety of ocular tissues was investigated. The 9,000g supernatant of ciliary body, retinal pigment epithelium-choroid, iris, retina and cornea, but not lens, exhibited reductase activity under anaerobic conditions when supplemented with 2-hydroxypyrimidine, an electron donor of aldehyde oxidase. Among these tissues, the highest activity was obse...

The in vivo conversion ratio of N-methylnicotinamide (NMN) to N-methyl-2-pyridone-5-carboxamide (2-PY) and N-methyl-4pyridone-3-carboxamide (4-PY) as a parameter for the estimation of aldehyde oxidase level in rats was examined. NMN and its pyridones (2-PY and 4-PY) are usually detected in the urine of rats. When we measured the ratio of the amount of pyridones to the total amount of NMN and py...

The in vivo conversion ratio of N-methylnicotinamide (NMN) to N-methyl-2-pyridone-5-carboxamide (2-PY) and N-methyl-4pyridone-3-carboxamide (4-PY) as a parameter for the estimation of aldehyde oxidase level in rats was examined. NMN and its pyridones (2-PY and 4-PY) are usually detected in the urine of rats. When we measured the ratio of the amount of pyridones to the total amount of NMN and py...

The in vivo conversion ratio of N-methylnicotinamide (NMN) to N-methyl-2-pyridone-5-carboxamide (2-PY) and N-methyl-4pyridone-3-carboxamide (4-PY) as a parameter for the estimation of aldehyde oxidase level in rats was examined. NMN and its pyridones (2-PY and 4-PY) are usually detected in the urine of rats. When we measured the ratio of the amount of pyridones to the total amount of NMN and py...