title: Prediction of the Candida antarctica lipase A protein structure by comparative modeling and site-directed mutagenesis.
abstract: A number of model structures of the CalA suggested by comparative modeling were tested by site-directed mutagenesis. Enzyme variants were created where amino acids predicted to play key roles for the lipase activity in the different models were replaced by an inert amino acid (alanine). The results from activity measurements of the overproduced and purified mutant enzymes indicate a structure where the active site consists of amino acid residues Ser184, His366, and Asp334 and in which there is no lid. This model can be used for future targeted modifications of the enzyme to obtain new substrate acceptance, better thermostability, and higher enantioselectivity.
authors.affiliation: Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm, Sweden.
authors.forename: Alex
authors.initials: A
authors.lastname: Kasrayan
authors.forename: Marco
authors.initials: M
authors.lastname: Bocola
authors.forename: Anders G
authors.initials: AG
authors.lastname: Sandström
authors.forename: Gaston
authors.initials: G
authors.lastname: Lavén
authors.forename: Jan-E
authors.initials: JE
authors.lastname: Bäckvall
mesh_terms: D002175:Candida / Q000201:enzymology; D020134:Catalytic Domain; D008049:Lipase / Q000737:chemistry; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed
chemical_list: D008049:Lipase