1qz3
From Proteopedia
CRYSTAL STRUCTURE OF MUTANT M211S/R215L OF CARBOXYLESTERASE EST2 COMPLEXED WITH HEXADECANESULFONATE
Structural highlights
FunctionEvolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe reaction mechanism of the esterase 2 (EST2) from Alicyclobacillus acidocaldarius was studied at the kinetic and structural level to shed light on the mechanism of activity and substrate specificity increase previously observed in its double mutant M211S/R215L. In particular, the values of kinetic constants (k1, k(-1), k2, and k3) along with activation energies (E1, E(-1), E2, and E3) were measured for wild type and mutant enzyme. The previously suggested substrate-induced switch in the reaction mechanism from kcat=k3 with a short acyl chain substrate (p-nitrophenyl hexanoate) to kcat=k2 with a long acyl chain substrate (p-nitrophenyl dodecanoate) was validated. The inhibition afforded by an irreversible inhibitor (1-hexadecanesulfonyl chloride), structurally related to p-nitrophenyl dodecanoate, was studied by kinetic analysis. Moreover the three-dimensional structure of the double mutant bound to this inhibitor was determined, providing essential information on the enzyme mechanism. In fact, structural analysis explained the observed substrate-induced switch because of an inversion in the binding mode of the long acyl chain derivatives with respect to the acyl- and alcohol-binding sites. A substrate-induced switch in the reaction mechanism of a thermophilic esterase: kinetic evidences and structural basis.,De Simone G, Mandrich L, Menchise V, Giordano V, Febbraio F, Rossi M, Pedone C, Manco G J Biol Chem. 2004 Feb 20;279(8):6815-23. Epub 2003 Nov 15. PMID:14617621[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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