Carboxylesterase type B explained

Carboxylesterase, type B is a family of evolutionarily related proteins that belongs to the superfamily of proteins with the Alpha/beta hydrolase fold.

Higher eukaryotes have many distinct esterases. The different types include those that act on carboxylic esters . Carboxyl-esterases have been classified into three categories (A, B and C) on the basis of differential patterns of inhibition by organophosphates. The sequence of a number of type-B carboxylesterases indicates^{[1] [2] [3]} that the majority are evolutionarily related. As is the case for lipases and serine proteases, the catalytic apparatus of esterases involves three residues (catalytic triad): a serine, a glutamate or aspartate and a histidine.

Examples

Human genes that encode proteins containing the carboxylesterase domain include:

• ACHE
• ARACHE
• BCHE
• CEL
• CES1
• CES2
• CES3
• CES4
• CES7
• CES8
• NLGN1
• NLGN2
• NLGN3
• NLGN4X
• NLGN4Y
• TG

See also

• Carboxylesterase

External links

• Carboxylesterases type-B in PROSITE

Notes and References

1. Myers M, Richmond RC, Oakeshott JG . On the origins of esterases . Mol. Biol. Evol. . 5 . 2 . 113–119 . 1988 . 3163407. 10.1093/oxfordjournals.molbev.a040485 . free .
2. Chatonnet A, Krejci E, Duval N, Vincens P, Massoulie J . Cholinesterase-like domains in enzymes and structural proteins: functional and evolutionary relationships and identification of a catalytically essential aspartic acid . Proc. Natl. Acad. Sci. U.S.A. . 88 . 15 . 6647–6651 . 1991 . 1862088 . 10.1073/pnas.88.15.6647 . 52145. 1991PNAS...88.6647K . free .
3. Sussman JL, Cygler M, Harel M, Silman I, Schrag JD, Doctor BP, Gentry MK . Relationship between sequence conservation and three-dimensional structure in a large family of esterases, lipases, and related proteins . Protein Sci. . 2 . 3 . 366–382 . 1993 . 8453375 . 2142374 . 10.1002/pro.5560020309.