aldehyde dehydrogenase 9 family, member A1 (aldehyde dehydrogenase 9, aldehyde dehydrogenase E3 isozyme, gamma-aminobutyraldehyde dehydrogenase, ALDH9A1, ALDH4, ALDH7, ALDH9)

Function

• converts gamma-trimethylaminobutyraldehyde into gamma-butyrobetaine
• catalyzes irreversible oxidation of a broad range of aldehydes to the corresponding acids (NAD-dependent)
• amine & polyamine biosynthesis; carnitine biosynthesis

4-trimethylammoniobutanal + NAD+ + H2O
               <-->
4-trimethylammoniobutanoate + NADH

an aldehyde + NAD+ + H2O <--> an acid + NADH

4-aminobutanal + NAD+ + H2O <--> 4-aminobutanoate + NADH

Kinetic parameters:

• KM=11 uM for 4-aminobutyraldehyde
• Optimum pH
  • about 9.4 with propionaldehyde as substrate
  • about 7.5 with 4-aminobutyraldehyde as substrate

Structure

• homotetramer
• N-terminus is blocked
• belongs to the aldehyde dehydrogenase family

Compartment

cytoplasm (putative)

Expression

• high expression in adult liver, skeletal muscle, & kidney
• low levels in heart, pancreas, lung & brain
• expressed in all regions of the brain
• expression levels are variable in the different CNS areas, highest levels in spinal cord, lowest in the occipital pole
• strongly expressed in human embryonic brain (gestational age 12 weeks)

More general terms

• aldehyde dehydrogenase

Database

• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:223
• OMIM: https://mirror.omim.org/entry/602733
• UniProt: http://www.uniprot.org/uniprot/P49189.html
• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=223