Project Details
Projekt
Directed evolution of transaldolases for novel specificities
Subject Area
Biochemistry
Term
from 2004 to 2011
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 5429743
Aldolases are powerful catalysts for asymmetric synthesis in that they control the creation of up to two new stereocenters, yet their natural substrate specificities and stereoselectivities are limiting. We aim to produce modified transaldolases with new donor substrate specificities and unnatural stereo-specificities by directed evolution, guided by information from protein structures of natural transaldolases. Because of mechanistic considerations, such protein modifications must involve active-site mutations that usually will be deleterious to catalytic activity, and therefore will require adjustment of catalytic residues by additional benign sequence changes. For diversity generation, DNA (family) shuffling, epPCR and localized cassette mutagenesis will be applied to sample a sufficiently large functional sequence space. This project will also develop efficient screening assays for novel, stereoselective aldol reactions and explore systematically the capability of mutant transaldolases for the asymmetric synthesis of enantiopure building blocks. The anticipated mechanistic insight in, as well as the functional engineering of, factors controlling stereodifferentiation of biocatalytic C-C bond forming reactions should provide knowledge of general significance and broaden the current scope of biocatalysis.
DFG Programme
Priority Programmes
