The catalytic triad of this esterase enzyme comprises residues Ser127, His403 and Asp391 in UniProtKB:P70665 [1,2].

1: The structure at 1.6 Angstroms resolution of the protein product of the At4g34215 gene from Arabidopsis thaliana. Bitto E, Bingman CA, McCoy JG, Allard ST, Wesenberg GE, Phillips GN Jr; Acta Crystallogr D Biol Crystallogr. 2005;61:1655-1661. PMID:16301800

2: Functionally defective germline variants of sialic acid acetylesterase in autoimmunity. Surolia I, Pirnie SP, Chellappa V, Taylor KN, Cariappa A, Moya J, Liu H, Bell DW, Driscoll DR, Diederichs S, Haider K, Netravali I, Le S, Elia R, Dow E, Lee A, Freudenberg J, De Jager PL, Chretien Y, Varki A, MacDonald ME, Gillis T, Behrens TW, Bloch D, Collier D, Korzenik J, Podolsky DK, Hafler D, Murali M, Sands B, Stone JH, Gregersen PK, Pillai S; Nature. 2010;466:243-247. PMID:20555325