Learn More
Baeyer–Villiger monooxygenase-catalysed reactions are attractive for industrial processes. Here we report on expanding the substrate scope of phenylacetone monooxygenase (PAMO). In order to introduce activity on alicyclic ketones in PAMO, we generated and screened a library of 1,500 mutants. Based on recently published structures of PAMO and its mutants, we(More)
Focused mutant library generation methods have been developed to improve mainly "localizable" enzyme properties such as activity and selectivity. Current multi-site saturation methods are restricted by the gene sequence, require subsequent PCR steps and/or additional enzymatic modifications. Here we report, a multiple site saturation mutagenesis method,(More)
Bacillus subtilis strains are used for extracellular expression of enzymes (i.e., proteases, lipases, and cellulases) which are often engineered by directed evolution for industrial applications. B. subtilis DB104 represents an attractive directed evolution host since it has a low proteolytic activity and efficient secretion. B. subtilis DB104 is hampered(More)
BACKGROUND Channel proteins like the engineered FhuA Δ1-159 often cannot insert into thick polymeric membranes due to a mismatch between the hydrophobic surface of the protein and the hydrophobic surface of the polymer membrane. To address this problem usually specific block copolymers are synthesized to facilitate protein insertion. Within this study in a(More)
Sequence saturation mutagenesis (SeSaM) is a conceptually novel and practically simple method that truly randomizes a target sequence at every single nucleotide position. A SeSaM experiment can be accomplished within 2-3 days and comprises four steps: generating a pool of DNA fragments with random length, 'tailing' the DNA fragments with universal base(More)
The psychrophilic protease subtilisin S41 from the Antarctic bacillus TA41, and two variants with two and seven amino acid substitutions were studied using molecular dynamics simulation at 283 and 363 K. The analysis of protein dynamics revealed that the average global flexibility of both variants was slightly higher than wild type at both 283 and 363 K.(More)
Phytase improves as a feed supplement the nutritional quality of phytate-rich diets (e.g., cereal grains, legumes, and oilseeds) by hydrolyzing indigestible phytate (myo-inositol 1,2,3,4,5,6-hexakis dihydrogen phosphate) and increasing abdominal absorption of inorganic phosphates, minerals, and trace elements. Directed phytase evolution was reported for(More)
A thermostable glucoamylase (TtcGA) from Thermoanaerobacter tengcongensis MB4 was successfully expressed in Escherichia coli. The full-length gene (2112 bp) encodes a 703-amino acid polypeptide including a predicted signal peptide of 21 residues. The recombinant mature protein was partially purified to 30-fold homogeneity by heat treatment and gel(More)
BACKGROUND Recently we reported a nanocontainer based reduction triggered release system through an engineered transmembrane channel (FhuA Delta1-160; Onaca et al., 2008). Compound fluxes within the FhuA Delta1-160 channel protein are controlled sterically through labeled lysine residues (label: 3-(2-pyridyldithio)propionic-acid-N-hydroxysuccinimide-ester).(More)
Solved crystal structures of P450 BM3 variants in complex with styrene provide on the molecular level a first explanation of how a positively charged surface residue inverts the enantiopreference of styrene epoxidation. The obtained insights into productive and non-productive styrene binding modes deepened our understanding of enantioselective epoxidation(More)