Glycerophosphodiester phosphodiesterase domain of Thermotoga maritime and similar proteins
This subfamily corresponds to the glycerophosphodiester phosphodiesterase domain (GDPD) present in Thermotoga maritime glycerophosphodiester phosphodiesterase (TmGDE, EC 18.104.22.168) and its uncharacterized homologs. Members in this family show high sequence similarity to Escherichia coli GP-GDE, which catalyzes the degradation of glycerophosphodiesters to produce sn-glycerol-3-phosphate (G3P) and the corresponding alcohols. TmGDE exists as a monomer that might be the biologically relevant form.
Comment:The catalytic mechanism of glycerophosphodiester phosphodiesterases is based on the metal ion-dependent general acid-base reaction.
Comment:Based on structure evidence and site-directed mutagenesis of Thermoanaerobacter tengcongensis glycerophosphodiester phosphodiesterase, the catalytic site consists of two conserved histidine residues which serve as general acid and general base in catalyzing the hydrolysis of the 3'-5' phosphodiester bond.