Protein
S-inosyl-L-homocysteine hydrolase
Organism
Methanocaldococcus jannaschii (strain ATCC 43067 / DSM 2661 / JAL-1 / JCM 10045 / NBRC 100440)
Function
Catalyzes the hydrolysis of S-inosyl-L-homocysteine (SIH) to L-homocysteine (Hcy) and inosine. Likely functions in a S-adenosyl-L-methionine (SAM) recycling pathway from S-adenosyl-L-homocysteine (SAH) produced from SAM-dependent methylation reactions. Can also catalyze the reverse reaction in vitro, i.e. the synthesis of SIH from Hcy and inosine. Is specific for SIH and inosine as it is unable to either hydrolyze SAH or synthesize SAH from adenosine and Hcy.
Similarity
Belongs to the adenosylhomocysteinase family.
Sequence
MYEVRDINLWKEGERKIQWAKQHMPVLNLIRERFKEEKPFKGITIGMALHLEAKTAVLAETLMEGGAEIAITGCNPLSTQDDVAAACAKKGMHVYAWRGETVEEYYENLNKVLDHKPDIVIDDGCDLIFLLHTKRTELLDNIMGGCEETTTGIIRLKAMEKEGALKFPVMDVNDAYTKHLFDNRYGTGQSALDGILRATNLLIAGKTVVVAGYGWCGRGVAMRAKGLGAEVVVTEVNPIRALEARMDGFRVMKMEKAAEIGDIFITTTGCKDVIRKEHILKMRNGAILANAGHFDNEINKKHLEELAKSIKEVRNCVTEYDLGNKKIYLLGEGRLVNLACADGHPCEVMDMSFANQALAAEYILKNHEKLEPRVYNIPYEQDLMIASLKLKAMGIEIDELTKEQKKYLEDWREGT