Glycan-functionalized Polymers and Biosensors
In collaboration with DWI Leibniz-Institut für Interaktive Materialien N-acetylglucosamine (GlcNAc) grafted glycopolymer brushes were produced on a solid silica surface via controlled polymerization. Monomeric GlcNAc was elongated to repetitive N-acetyl-lactosamine (LacNAc) units by applying appropriate enzymes (glycosyltransferases). The multivalent glyco-brushes function as a recognition platform for lectins, e.g. GS-II (Griffonia simplicifolia lectin) and ECL (Erythrina cristagalli lectin).
According to this technology, gold surfaces were modified in cooperation with the Institute of Materials in Electrical Engineering. The brush length was controlled by the duration of polymerization and evaluated by atomic force microscopy (AFM). The GlcNAc-residues were specifically converted by a β4-galactosyl- and a α3-galactosyltransferase to a clinically important glycosylation motif (Galili or α3-Gal epitope). This multivalent gold chip enables the binding analysis of bacterial toxin A from Clostridium difficile (TcdA) via electrochemical impedance spectroscopy (EIS) and functions thereby as a biosensor. A biosensor for glycosyltransferases was developed by the layer-by-layer immobilization of a multivalent neo-glycoprotein (NGP) on a gold chip. The transfer of Fucose on the NGP by a bacterial fucosyltransferase (FucT) and the subsequent binding of the fucose-specific Aleuria aurantia lectin (AAL) were measured by EIS. This first glycosyltransferase biosensor is of interest in pathogen and cancer diagnostics.
Publikationen zur Synthese und Anwendung von Glykopolymeren und Biosensoren:
Lazar, J., Park, H., Rosencrantz, R.R., Böker, A., Elling, L., Schnakenberg, U., 2015. Evaluating the Thickness of Multivalent Glycopolymer Brushes for Lectin Binding. Macromol. Rapid Commun. 36, 1472-1478. https://doi.org/10.1002/marc.201500118.
Park, H., Rosencrantz, R.R., Elling, L., Böker, A., 2015. Glycopolymer Brushes for Specific Lectin Binding by Controlled Multivalent Presentation of N-Acetyllactosamine Glycan Oligomers. Macromol. Rapid Commun. 36, 45-54. https://doi.org/10.1002/marc.201400453.
Lazar, J., Rosencrantz, R.R., Elling, L., Schnakenberg, U., 2016. Simultaneous Electrochemical Impedance Spectroscopy and Localized Surface Plasmon Resonance in a Microfluidic Chip: New Insights into the Spatial Origin of the Signal. Anal. Chem. 88, 9590-9596. https://doi.org/10.1021/acs.analchem.6b02307.
Park, H., Walta, S., Rosencrantz, R.R., Korner, A., Schulte, C., Elling, L., Richtering, W., Böker, A., 2016. Micelles from self-assembled double-hydrophilic PHEMA-glycopolymer-diblock copolymers as multivalent scaffolds for lectin binding. Polymer Chemistry 7, 878-886. https://doi.org/10.1039/C5PY00797F.
Rosencrantz, R.R., Nguyen, V.H., Park, H., Schulte, C., Böker, A., Schnakenberg, U., Elling, L., 2016. Lectin binding studies on a glycopolymer brush flow-through biosensor by localized surface plasmon resonance. Anal. Bioanal. Chem. 408, 5633-5640. https://doi.org/10.1007/s00216-016-9667-9
Bojarová, P., Tavares, M.R., Laaf, D., Bumba, L., Petrasková, L., Konefal, R., Blahova, M., Pelantová, H., Elling, L., Etrych, T., Chytil, P., Křen, V., 2018. Biocompatible glyconanomaterials based on HPMA-copolymer for specific targeting of galectin-3. J Nanobiotechnology 16, 73. https://doi.org/10.1186/s12951-018-0399-1.
Freichel, T., Laaf, D., Hoffmann, M., Konietzny, P.B., Heine, V., Wawrzinek, R., Rademacher, C., Snyder, N.L., Elling, L., Hartmann, L., 2019. Effects of linker and liposome anchoring on lactose-functionalized glycomacromolecules as multivalent ligands for binding galectin-3. RSC Advances 9, 23484-23497. https://doi.org/10.1039/C9RA05497A.
Filipová, M., Bojarová, P., Rodrigues Tavares, M., Bumba, L., Elling, L., Chytil, P., Gunár, K., Křen, V., Etrych, T., Janoušková, O., 2020. Glycopolymers for Efficient Inhibition of Galectin-3: In Vitro Proof of Efficacy Using Suppression of T Lymphocyte Apoptosis and Tumor Cell Migration. Biomacromolecules 21, 3122-3133. https://doi.org/10.1021/acs.biomac.0c00515.
Freichel, T., Heine, V., Laaf, D., Mackintosh, E.E., Sarafova, S., Elling, L., Snyder, N.L., Hartmann, L., 2020. Sequence-Defined Heteromultivalent Precision Glycomacromolecules Bearing Sulfonated/Sulfated Nonglycosidic Moieties Preferentially Bind Galectin-3 and Delay Wound Healing of a Galectin-3 Positive Tumor Cell Line in an In Vitro Wound Scratch Assay. Macromol. Biosci. 20, 2000163. https://doi.org/10.1002/mabi.202000163.
Hoffmann, M., Gau, E., Braun, S., Pich, A., Elling, L., 2020. Enzymatic Synthesis of 2-(beta-Galactosyl)-ethyl Methacrylate by beta-Galactosidase from Pyrococcus woesei and Application for Glycopolymer Synthesis and Lectin Studies. Biomacromolecules 21, 974-987. https://doi.org/10.1021/acs.biomac.9b01647.
Tavares, M.R., Blahová, M., Sedlakova, L., Elling, L., Pelantová, H., Konefal, R., Etrych, T., Křen, V., Bojarová, P., Chytil, P., 2020. High-Affinity N-(2-Hydroxypropyl)methacrylamide Copolymers with Tailored N-Acetyllactosamine Presentation Discriminate between Galectins. Biomacromolecules 21, 641-652. https://doi.org/10.1021/acs.biomac.9b01370.
Heine, V., Kremers, T., Menzel, N., Schnakenberg, U., Elling, L., 2021. Electrochemical Impedance Spectroscopy Biosensor Enabling Kinetic Monitoring of Fucosyltransferase Activity. ACS Sensors 6, 1003-1011. https://doi.org/10.1021/acssensors.0c02206.