Family Report for: OtherNon-catalytic_C

Among COesterase PF00135 a number of proteins seem to lack active site residues but have not yet been characterized. They are not related to the known families of non-catalytic COesterase (neuroligins, neurotactin, gliotactin, glutactin) They could be pseudo genes or sequencing errors

Title: Cholinesterase-like domains in enzymes and structural proteins: functional and evolutionary relationships and identification of a catalytically essential aspartic acid
Krejci E, Duval N, Chatonnet A, Vincens P, Massoulie J
Ref: Proceedings of the National Academy of Sciences of the United States of America, 88:6647, 1991 : PubMed
Abstract


ESTHER: Krejci_1991_Proc.Natl.Acad.Sci.U.S.A_88_6647
PubMedSearch: Krejci 1991 Proc.Natl.Acad.Sci.U.S.A 88 6647
PubMedID: 1862088

Abstract

Primary sequences of cholinesterases and related proteins have been systematically compared. The cholinesterase-like domain of these proteins, about 500 amino acids, may fulfill a catalytic and a structural function. We identified an aspartic acid residue that is conserved among esterases and lipases (Asp-397 in Torpedo acetylcholinesterase) but that had not been considered to be involved in the catalytic mechanism. Site-directed mutagenesis demonstrated that this residue is necessary for activity. Analysis of evolutionary relationships shows that the noncatalytic members of the family do not constitute a separate subgroup, suggesting that loss of catalytic activity occurred independently on several occasions, probably from bifunctional molecules. Cholinesterases may thus be involved in cell-cell interactions in addition to the hydrolysis of acetylcholine. This would explain their specific expression in well-defined territories during embryogenesis before the formation of cholinergic synapses and their presence in noncholinergic tissues.