Glycerophosphoryl diester phosphodiesterase hydrolyzes deacylated phospholipids to G3P and the corresponding alcohols. Binds human IgA, IgD and the Fc portion of IgG but not IgM, which may contribute to evasion of the human immune system. a sn-glycero-3-phosphodiester + H2O = an alcohol + H(+) + sn-glycerol 3-phosphate Has also been identified in cell outer membrane, but this may be incorrect (PubMed:9826352, PubMed:9317025). Palmitoylated upon expression of a fusion protein with first 40 residues fused to PhoA in E.coli. Immunization of rabbits with this protein partially protects against subsequent intradermal challenge, suggesting it may be a viable vaccine candidate (PubMed:9826352). Recognized by sera from 39/43 syphilis patients, it shows promise as a diagnostic antigen (PubMed:12904373). The outer membrane of T.pallidum has no lipopolysaccharides, few proteins and is a fluid and very fragile bilayer. Its lack of surface antigenicity is thought to contribute to the ability of the pathogen to evade the human immune system. Belongs to the glycerophosphoryl diester phosphodiesterase family.