Henke, ErikBornscheuer, Uwe TheoSchmid, Rolf D.Pleiss, Jürgen2006-06-012016-03-312006-06-012016-03-312003262546825http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-26732http://elib.uni-stuttgart.de/handle/11682/848http://dx.doi.org/10.18419/opus-831Carboxylesterases containing the sequence motif GGGX catalyze hydrolysis of esters of chiral tertiary alcohols, albeit at only low to moderate enantioselectivity towards three model substrates (linalyl acetate, methyl-1-pentin-1-yl acetate, 2-phenyl-3-butin-2-yl acetate). In order to understand the molecular mechanism of enantiorecognition and to improve enantioselectivity towards this interesting substrate class, the interaction of both enantiomers with the substrate binding sites of acetylcholinesterases and p-nitrobenzyl esterase from Bacillus subtilis was modeled and correlated to experimental enantioselectivity. For all substrate-enzyme pairs, enantiopreference and ranking by enantioselectivity could be predicted by the model. In p-nitrobenzyl esterase, one of the key residues in determining enantioselectivity was G105: exchange of this residue by alanine led to a six-fold increase of enantioselectivity (E=19) towards 2-phenyl-3-butin-2-yl acetate. However, the effect of this mutation is personalized: towards the substrate linalyl acetate, the same mutant had a reversed enantiopreference. Thus, depending on the substrate structure, the same mutant had either increased enantioselectivity or opposite enantiopreference compared to wild type enzyme.eninfo:eu-repo/semantics/openAccessBioinformatik , Molekulare Bioinformatik , Proteindesign , Carboxylesterase540enantioselectivity , enzyme catalysis , molecular modeling , protein design , tertiary alcoholspreprint2015-12-10