A5002692942- Microbial bioremediation and biosurfactants
- Environmental Chemistry and Analysis
- Plant biochemistry and biosynthesis
- Enzyme Catalysis and Immobilization
- Pesticide and Herbicide Environmental Studies
- Biochemical and biochemical processes
- Pharmacological Effects of Natural Compounds
- Microbial Natural Products and Biosynthesis
- Biopolymer Synthesis and Applications
- Microbial Metabolic Engineering and Bioproduction
- Electrochemical sensors and biosensors
- Biochemical Acid Research Studies
- Drug Transport and Resistance Mechanisms
- Natural product bioactivities and synthesis
- Nematode management and characterization studies
- Bacterial Genetics and Biotechnology
- Microbial metabolism and enzyme function
- Pharmacogenetics and Drug Metabolism
- Tryptophan and brain disorders
- Organic and Inorganic Chemical Reactions
- Chemical Synthesis and Analysis
- Essential Oils and Antimicrobial Activity
- Polyamine Metabolism and Applications
- Microbial Community Ecology and Physiology
- Metal complexes synthesis and properties
Givaudan (Switzerland)
2012-2024
ETH Zurich
2000-2002
École Polytechnique Fédérale de Lausanne
1997-2001
Lonza (Switzerland)
1997-1998
Laccases (EC 1.10.3.2) are multi-copper oxidases that catalyse the one-electron oxidation of a broad range compounds including substituted phenols, arylamines and aromatic thiols to corresponding radicals. Owing their substrate range, copper-containing laccases versatile biocatalysts, capable oxidizing numerous natural non-natural industry-relevant compounds, with water as sole by-product. In present study, 10 11 oxidases, hitherto considered be laccases, from fungi, plant bacterial origin...
The Escherichia coli tauD gene is required for the utilization of taurine (2-aminoethanesulfonic acid) as a sulfur source and expressed only under conditions sulfate starvation. sequence relatedness TauD protein to α-ketoglutarate-dependent 2,4-dichlorophenoxyacetate dioxygenase Alcaligenes eutrophus suggested that an catalyzing oxygenolytic release sulfite from (van der Ploeg, J. R., Weiss, M. A., Saller, E., Nashimoto, H., Saito, N., Kertesz, Leisinger, T. (1996) Bacteriol. 178,...
The Escherichia coli ssuEADCB gene cluster is required for the utilization of alkanesulfonates as sulfur sources, and expressed under conditions sulfate or cysteine starvation. SsuD SsuE proteins were overexpressed characterized. was purified to homogeneity an N-terminal histidine-tagged fusion protein. Native a homodimeric enzyme Mr 58,400, which catalyzed NAD(P)H-dependent reduction FMN, but it also able reduce FAD riboflavin. protein >98% purity using cation exchange, anion hydrophobic...
The potential of biotechnology by means biocatalysis or biosynthesis in organic synthesis is far from being fully exploited. For this reason a group life science companies active pharmaceuticals, flavour and fragrance, vitamin fine chemicals businesses describe some examples the use enzymes industrial discuss why are still exception rather than rule synthesis.
In an oxygen-dependant reaction, tryptophan 7-halogenase (PrnA) regioselectively chlorinates (1) at the 7-position to yield 2. During purification of halogenase, a flavin reductase, as second protein component, was detected in addition NADH and FAD; this is also required for reaction.
ABSTRACT The Escherichia coli tauABCD and ssuEADCB gene clusters are required for the utilization of taurine alkanesulfonates as sulfur sources expressed only under conditions sulfate or cysteine starvation. tauD ssuD encode an α-ketoglutarate-dependent dioxygenase a reduced flavin mononucleotide-dependent alkanesulfonate monooxygenase, respectively. These enzymes responsible desulfonation alkanesulfonates. amino acid sequences SsuABC TauABC exhibit similarity to those components ATP-binding...
Abstract Alicyclobacillus acidocaldarius Squalene Hopene Cyclase was evolved to a biocatalyst suitable for (−)‐Ambrox production at industrial scale. One round of random mutagenesis led the identification three variants with ( E , )‐homofarnesol conversion properties improved about 1.5‐ 10‐fold over that wild type enzyme. Eight distinct amino acid mutations were identified overall; only one mutation active site Each contained two or 631 acids polypeptide chain. Mutations responsible...
Squalene-hopene cyclases (SHCs) have great potential for the industrial synthesis of enantiopure cyclic terpenoids. A limitation SHC catalysis has been enzymes' strict (S)-enantioselectivity at stereocenter formed after first cyclization step. To gain enantio-complementary access to valuable monocyclic terpenoids, an SHC-wild-type library including 18 novel homologs was set up. previously not described (AciSHC) found synthesize small amounts (R)-γ-dihydroionone from (E/Z)-geranylacetone....
In einer sauerstoffabhängigen Reaktion chloriert die Tryptophan-7-Halogenase PrnA Tryptophan 1 regioselektiv an der 7-Position unter Bildung von 2. Bei Reinigung Halogenase stellte sich heraus, dass für neben NADH auch FAD und eine Flavin-Reduktase (Bildung FADH2) benötigt werden.
Abstract All eight theoretical stereoisomers of (10 S )‐Ambrox have been synthesized by enzymatic polycyclization the four geometric isomers homofarnesol with selected squalene hopene cyclases. This includes highly strained (+)‐(8 ,9 S)‐ Ambrox, an isomer historically considered unlikely to exist. The enantiomeric R )‐series has prepared a combination diastereoselective synthesis and preparative chiral HPLC. Thus, for first time, sensory properties all but one Ambrox are presented. results...
Twenty-three Escherichia coli strains were tested for their ability to use taurine, methanesulfonate, L-cysteate and other alkanesulfonates as sole sulfur sources growth. One strain was unable any of the offered growth but grew with sulfate. Seven (class I) used this purpose, not methanesulfonate or L-cysteate. A further seven II) all compounds tested, except L-cysteate, eight III) utilized sources. Sulfur assimilation from absolutely dependent on ssuEADCB operon that encodes an...
Abstract The mechanism and substrate specificity of alkanesulfonate monooxygenase (SsuD) was investigated by combining molecular dynamics simulations, docking, a comprehensive quantitative structure activity relationships (QSAR) analysis. FMNH2 dependent undergoes dynamic conformational change the active site, passing from closed to an open state. As consequence, substrates have access site cofactor is then regenerated associated oxidoreductase FMN reductase SsuE.. Computational analysis...
(–)-Ambrox, the most prominent olfactive component of ambergris, is one widely used biodegradable fragrance ingredients. It traditionally produced from diterpene sclareol chemically modified and cyclized into (–)-ambrox. The availability new feedstock (E)-β-farnesene by fermentation opened routes to (E,E)-homofarnesol as a precursor Combining chemical transformation its enzymatic cyclization with an engineered Squalene Hopene Cyclase provided sustainable route for production (–)-ambrox at...
Abstract Squalene–hopene cyclases (SHCs) have great potential for the industrial synthesis of enantiopure cyclic terpenoids. A limitation SHC catalysis has been enzymes’ strict (S)‐enantioselectivity at stereocenter formed after first cyclization step. To gain enantio‐complementary access to valuable monocyclic terpenoids, an SHC‐wild‐type library including 18 novel homologs was set up. previously not described ( Aci SHC) found synthesize small amounts (R)‐γ‐dihydroionone from...