Evolution, expression, and substrate specificities of aldehyde oxidase enzymes in eukaryotes

Area of Science:

• Biochemistry
• Enzymology
• Pharmacology

Background:

• Aldehyde oxidases (AOXs) are molybdo-flavoenzymes involved in xenobiotic metabolism.
• Mammalian species exhibit varying numbers of functional AOX genes, from one in humans to four in rodents.
• The physiological significance of these diverse AOX complements remains largely unknown.

Purpose of the Study:

• To review the expression patterns of mammalian aldehyde oxidase enzymes.
• To elucidate the tissue-specific functions and substrate specificities of various AOX enzymes.
• To highlight current understanding of the physiological roles of AOX enzymes.

Main Methods:

• Literature review of existing studies on aldehyde oxidases.
• Comparative analysis of AOX gene complements across different mammalian species.
• Discussion of enzyme kinetics and substrate profiling data.

Main Results:

• AOX enzymes catalyze the hydroxylation of heterocycles and oxidation of aldehydes.
• Significant differences exist in AOX gene numbers and enzyme functions between humans and rodents.
• AOX enzymes are primarily expressed in the liver and are crucial for drug and xenobiotic metabolism.

Conclusions:

• Mammalian aldehyde oxidases play critical roles in detoxification and metabolic pathways.
• Further research is needed to fully understand the physiological relevance of diverse AOX enzyme repertoires.
• Understanding AOX function is vital for drug development and personalized medicine.