608513-52-6Relevant academic research and scientific papers
Natural diversity to guide focused directed evolution
Jochens, Helge,Bornscheuer, Uwe T.
, p. 1861 - 1866 (2010)
Simultaneous multiple site-saturation mutagenesis was performed at four active-site positions of an esterase from Pseudomonas fluorescens to improve its ability to convert 3-phenylbutyric acid esters (3-PBA) in an enantioselective manner. Based on an appropriate codon choice derived from a structural alignment of 1751 sequences of α/β-hydrolase fold enzymes, only those amino acids were considered for library creation that appeared frequently in structurally equivalent positions. Thus, the number of mutants to be screened could be substantially reduced while the number of functionally intact variants was increased. Whereas the wild-type esterase showed only marginal activity and poor enantioselectivity (Etrue=3.2) towards 3-PBA-ethyl ester, a significant number of hits with improved rates (up to 240-fold) and enantioselectivities (up to Etrue=80) were identified in these "smart" libraries.
A combination of in vivo selection and cell sorting for the identification of enantioselective biocatalysts
Fernandez-Alvaro, Elena,Snajdrova, Radka,Jochens, Helge,Davids, Timo,Boettcher, Dominique,Bornscheuer, Uwe T.
, p. 8584 - 8587 (2011/11/07)
The "carrot and stick" principle could be combined with cell sorting to enable the selection of enantioselective esterase variants from a mutant library. Hence, the enormous diversity generated in directed evolution experiments is now easily accessible by this high-throughput system. In line with the principle, the hydrolysis of 1 glycerin supports cell growth, whereas the hydrolysis of 2 leads to cell death. Copyright
