prof. dr. G.J. Poelarends
The research of Prof. dr. G.J. Poelarends is aimed at the design and selection of novel biocatalysts and biosynthetic pathways for the production of pharmaceutically relevant products. One area of interest is the selection, characterization, and development of new biocatalysts for stereoselective reactions that lead to substituted α- and β-amino acids and other amino compounds with biologically important properties. Another area of interest is the development of enantioselective proline-based biocatalysts for general alkylation, Michael addition, and aldol reactions as broadly useful synthetic bond-forming methodologies for the production of pharmaceuticals and fine chemicals. Finally, we work on the characterization and optimization of promiscuous protein functions, which will contribute to expanding our knowledge of the parameters involved in natural and laboratory enzyme evolution.
We are currently working on the following projects:
- discovery and engineering of proline-based biocatalysts (e.g., 4-oxalocrotonate tautomerase, 4-OT) for new bond-forming reactions
- discovery and engineering of C-N lyases for asymmetric synthesis of noncanonical amino acids
- discovery and engineering of ene- and nitroreductases for cascade synthesis
- discovery and mechanistic characterization of cofactor-independent oxygenases
- development of hybrid catalysts
Two key projects in the area of protein engineering and biocatalysis:
(I) Efficient chemo-enzymatic synthesis of aspartic acid derivatives, which are highly valuable as tools for neurobiological research and as chiral building blocks for pharma- and neutraceuticals
Prof. Dr. G.J. Poelarends (email@example.com)
This project focuses on the identification, characterization, and development of new biocatalysts for stereo- and regioselective addition reactions that lead to optically active α-amino acids. In collaboration with other groups at the University of Groningen, we have developed various enzymatic routes (using ammonia lyases) for the selective synthesis of a wide variety of substituted aspartic acids. These non-proteinogenic amino acids are highly valuable as tools for (neuro)biological research and as chiral building blocks for pharmaceuticals and food additives (e.g. dipeptide sweeteners). We have also employed laboratory evolution strategies to design ammonia lyases with improved catalytic activity, selectivity and/or an expanded substrate spectrum. Further work is currently underway to develop and apply engineered ammonia lyases for the efficient chemo-enzymatic synthesis of various new amino compounds, including derivatives of L-threo-3-(benzyloxy)aspartate (L-TBOA) and L-threo-3-benzylaspartate, important inhibitors of glutamate transporters in the central nervous system.
(1) de Villiers, J., de Villiers, M., Geertsema, E.M., Raj, H., and Poelarends, G.J. (2015) Chemoenzymatic synthesis of ortho-, meta- and para-substituted derivatives of L-threo-3-benzyloxyaspartate, an important glutamate transporter blocker. ChemCatChem. 7:1931-1934.
(2) Raj, H., Szymanski, W., de Villiers, J., Puthan Veetil, V., Quax, W.J., Shimamoto, K., Janssen, D.B., Feringa, B.L., and Poelarends, G.J. (2013) Kinetic resolutions and stereoselective synthesis of 3-substituted aspartic acids using engineered methylaspartate ammonia lyases. Chem. Eur. J. 19:11148-11152.
(3) Puthan Veetil, V., Raj, H., de Villiers, M., Tepper, P.G., Dekker, F.J., Quax, W.J., and Poelarends, G.J. (2013) Enantioselective synthesis of N-substituted aspartic acids using an engineered variant of methylaspartate ammonia lyase. ChemCatChem. 5:1325-1327.
(4) Raj, H., Szymański, W., de Villiers, J., Rozeboom, H.J., Puthan Veetil, V., Reis, C.R., de Villiers, M., Dekker, F.J., de Wildeman, S., Quax, W.J., Thunnissen, A.-M.W.H., Feringa, B.L., Janssen, D.B., and Poelarends, G.J. (2012) Engineering methylaspartate ammonia lyase for the asymmetric synthesis of unnatural amino acids. Nat. Chem. 4:478-484.
(II) Enzymatic synthesis of y-nitroaldehydes, versatile and practical precursors for important GABA analogues
Prof. Dr. G.J. Poelarends (firstname.lastname@example.org)
This project aims to develop enantioselective proline-based biocatalysts for general alkylation, Michael addition, and aldol reactions as broadly useful synthetic bond-forming methodologies for the production of pharmaceuticals and fine chemicals. Attention has been focussed on the use of tautomerases in asymmetric C-C bond formation. Using 4-oxalocrotonate tautomerase (4-OT), which has the unique feature of using a nucleophilic amino-terminal proline in catalysis, we have recently developed efficient protocols for enantioselective Michael-type reactions of a variety of aldehydes with various nitroolefins. These reactions yield important chiral building blocks (y-nitroaldehydes) for the synthesis of various y-aminobutyric acid (GABA) analogues such as marketed pharmaceuticals Baclofen, Pregabalin, Phenibut, Rolipram, and new derivatives thereof, which are valuable as tools for neurobiology research. Further work is currently underway applying directed evolution to 4-OT and other tautomerases to increase the activity and scope of these proline-based enzymes in the synthesis of GABA precursors.
(1) Van der Meer et al. (2016) Using mutability landscapes of a promiscuous tautomerase to guide the engineering of enantioselective Michaelases. Nat. Commun. 7:10911
(2) Poddar, H., Rahimi, M., Geertsema, E.M., Thunnissen, A.M.W.H., and Poelarends, G.J. (2015) Evidence for formation of an enamine species during aldol and Michael-type addition reactions promiscuously catalyzed by 4-oxalocrotonate tautomerase. ChemBioChem. 16:738-741.
(3) Geertsema, E.M., and Poelarends, G.J. (2014) Enzymatic carbon-carbon bond-forming Michael-type additions. In K. Faber, W.-D. Fessner, and N. Turner (eds.), Science of Synthesis: Biocatalysis in Organic Synthesis, volume 2, pp. 313-334. Thieme Chemistry, Stuttgart, Germany.
(4) Geertsema, E.M., Miao, Y., Tepper, P.G., de Haan, P., Zandvoort, E., Poelarends, G.J. (2013) Biocatalytic Michael-type additions of acetaldehyde to nitroolefins with the proline-based enzyme 4-oxalocrotonate tautomerase yielding enantioenriched y-nitroaldehydes. Chem. Eur. J. 19:14407-14410.
(5) Miao, Y., Geertsema, E.M., Tepper, P.G., Zandvoort, E., and Poelarends, G.J. (2013) Promiscuous catalysis of asymmetric Michael-type additions of linear aldehydes to β-nitrostyrene by the proline-based enzyme 4-oxalocrotonate tautomerase. ChemBioChem. 14:191-194;
(6) Zandvoort, E., Geertsema, E.M., Baas, B.J., Quax, W.J., and Poelarends, G.J. (2012) Bridging between organocatalysis and biocatalysis: asymmetric addition of acetaldehyde to β-nitrostyrenes catalyzed by a promiscuous proline-based tautomerase. Angew. Chem. Int. Ed. 51:1240-1243.
Current research team:
Pieter Tepper (Technician)
Jielin Zhang (PhD student)
Lieuwe Biewenga (PhD student)
Chao Guo (PhD student)
Laura Florez-Sampedro (PhD student; in collaboration with Prof. Barbro Melgert)
Haigen Fu (PhD student)
Mohammad Saifuddin (Post-doc)
Saravanan Thangavelu (Post-doc)
ShanShan Song (PhD student, in collaboration with Prof. Barbro Melgert and Prof. Peter Olinga)
Andreas Kunzendorf (PhD student)
Eleonora Grandi (PhD student)
Marie-Catherine Sigmund (PhD student)
Guangcai Xu (PhD student)
Michele Crotti (Post-doc)
Mohammad Faizan Bath (PhD student)
Fabiola Zuchi (PhD student)
Alejandro Prats Lujan (PhD student)
Dr. Vinod Puthan Veetil (former PhD student and post-doc; PhD thesis defence on July 13, 2012)
Dr. Ellen Zandvoort (former PhD student; PhD thesis defence on December 7, 2012)
Dr. Marianne de Villiers (former Post-doc; October 2010-October 2012)
Dr. Anna Wasiel (former PhD student; PhD thesis defence on April 19, 2013)
Dr. Jandré de Villiers (former Post-doc; October 2010-October 2013)
Dr. Hans Raj (former PhD student and post-doc; PhD thesis defence on October 11, 2013)
Dr. Edzard Geertsema (former Post-doc; September 2010-September 2014)
Dr. Bert-Jan Baas (former PhD student, PhD thesis defence on December 22, 2014)
Dr. Yufeng Miao (former PhD student, PhD thesis defence on June 5, 2015)
Dr. Sabry Hamdy Hamed Younes (former Post-doc and guest researcher; October 2013-December 2015)
Dr. Mehran Rahimi (former PhD student, PhD thesis defence on May 27th, 2016)
Dr. Jan Ytzen van der Meer (former PhD student, PhD thesis defence on October 7, 2016)
Dr. Yan Ni (former Post-doc; July 2016-July 2017)
Dr. Tjie Kok Go (former PhD student, PhD thesis defence on January 25th, 2019)
Dr. Jielin Zhang (former PhD student, PhD thesis defence on August 26th, 2019)
Harshwardhan Poddar (awaiting PhD thesis defence)
Mohammad Zainal Abidin (awaiting PhD thesis defence)
|Last modified:||08 June 2019 5.13 p.m.|