AlkB

AlkB protein is a protein induced during an adaptive response and is involved in the direct reversal of alkylation damage. AlkB specifically removes alkylation damage to single stranded (SS) DNA caused by SN2 type of chemical agents. It efficiently removes methyl groups from 1-methyl adenines, 3-methyl cytosines in SS DNA. AlkB is a alpha-ketoglutarate-dependent hydroxylase, a superfamily non-haem iron-containing proteins. It oxidatively demethylates the DNA substrate. Demethylation by AlkB is accompanied with release of CO2, succinate, and formaldehyde. AlkB protein is a protein induced during an adaptive response and is involved in the direct reversal of alkylation damage. AlkB specifically removes alkylation damage to single stranded (SS) DNA caused by SN2 type of chemical agents. It efficiently removes methyl groups from 1-methyl adenines, 3-methyl cytosines in SS DNA. AlkB is a alpha-ketoglutarate-dependent hydroxylase, a superfamily non-haem iron-containing proteins. It oxidatively demethylates the DNA substrate. Demethylation by AlkB is accompanied with release of CO2, succinate, and formaldehyde. There are nine human homologs of AlkB. They are: ABH3, like E. coli AlkB, is specific for SS DNA and RNA whereas ABH2 has higher affinity for damages in double-stranded DNA. ALKBH8 has a RNA recognition motif, a methyltransferase domain, and an AlkB-like domain. The methyltransferase domain generates the wobble nucleoside 5-methoxycarbonylmethyluridine (mcm5U) from its precursor 5-carboxymethyluridine (cm5U). The AlkB-like domain generates (S)-5-methoxycarbonylhydroxymethyluridine (mchm5U)in Gly-tRNA-UCC. FTO, which is associated with obesity in humans, is the first identified RNA demethylase. It demethylates N6-methyladenosine in mRNA.