Area of research:
A reliable and reproducible quantification and detailed characterization of interactions between a biomedically relevant protein and its synthetic carbohydrate ligand can provide new information for the design of better diagnostic and therapeutic tools. A high sensitivity and specificity are essential requirements for the feasibility of the analytical method. These parameters can be difficult to achieve for highly complex systems such as lectin-carbohydrate complexes. The binding site of the lectin receptor is often shallow and conserved across a large lectin class, making it difficult to develop carbohydrate ligands with a high selectivity. On the other hand, carbohydrate diagnostics and therapeutics offer a great advantage for detecting the biological activity of the lectin receptor, which cannot be achieved with antibodies. This work focuses on new methods of studying lectin-carbohydrate interactions, primarily on the model biological system of galectins important for their involvement in a number of diseases, especially cancer.
The first part of the project is dedicated to the development and optimization of a new method of characterizing protein-carbohydrate interactions, Biolayer Interferometry (BLI). The immobilization of galectin on the biosensor is of utmost importance for maintaining its biological activity. This project addresses an innovative method of specific labeling of galectins for immobilization using a so-called “Avi-tag”. The in vivo labeled galectin constructs carry a single biotin molecule. In the frame of the project, a library of synthetic glycoconjugates will be tested as ligands of these galectins, which will be prepared by chemo-enzymatic synthesis and purified by size exclusion chromatography (SEC) and newly developed methods of preparative high performance liquid chromatography (HPLC).
In the second part of the project, the interaction of selected synthetic glycoconjugates with galectins will be investigated by Nuclear Magnetic Resonance (NMR). This part will involve the preparation of 15N-labeled galectins. Synthetic ligands will be selected on the basis of a surprising selectivity or a particularly high avidity. The goal of the analysis will be to reveal structural and affinity patterns and to define important structural parameters for further development of neo-glycoconjugates as effective cancer therapeutics.
The main task of the student will be to perform HPLC, BLI and NMR measurements, analyze the obtained data, perform chemo-enzymatic preparation of neo-glycoconujgates and their purification. Furthermore, the production of labeled galectins will be optimized to ensure efficient immobilization on the BLI biosensor chips.
P. Nekvasilová, N. Kulik, N. Rychlá, H. Pelantová, L. Petrásková, Z. Bosáková, J. Cvačka, K. Slámová, V. Křen, P. Bojarová, Adv. Synth. Catal. 2020, 362, 4138-4150.
S. Bertuzzi, A. Gimeno, A. Martinez-Castillo, M. G. Lete, S. Delgado, C. Airoldi, M. R. Tavares, M. Bláhová, P. Chytil, V. Křen, N. G. A. Abrescia, A. Ardá, P. Bojarová, J. Jiménez-Barbero, Int. J. Mol. Sci. 2021, 22, 6000.
Features of an ideal candidate:
Required: MSc. or equivalent in Analytical chemistry, Physics or a related field, good command of English
Beneficial: Solid background in Biological and Analytical methods for analysis of interactions within biological systems, Bio-Physical methods. Experience with HPLC, Surface plasmon resonance or Bio-layer interferometry and NMR analysis will be an advantage.