Structural, Thermal, and Storage Stability of <i>Rapana Thomasiana</i> Hemocyanin in the Presence of Cholinium-Amino Acid-Based Ionic Liquids
Maya Guncheva,
Krassimira Idakieva,
Svetla Todinova,
Denitsa Yancheva,
Tsvetelina Paunova-Krasteva,
Paula Ossowicz,
Ewa Janus
Affiliations
Maya Guncheva
Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Bl. 9, 1113 Sofia, Bulgaria
Krassimira Idakieva
Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Bl. 9, 1113 Sofia, Bulgaria
Svetla Todinova
Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Str. 21, 1113 Sofia, Bulgaria
Denitsa Yancheva
Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Bl. 9, 1113 Sofia, Bulgaria
Tsvetelina Paunova-Krasteva
The Stefan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Acad. G. Bonchev Str. Bl. 26, 1113 Sofia, Bulgaria
Paula Ossowicz
Department of Chemical Organic Technology and Polymeric Materials, Szczecin, Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology, Piastów Ave. 42, 71-065 Szczecin, Poland
Ewa Janus
Department of Chemical Organic Technology and Polymeric Materials, Szczecin, Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology, Piastów Ave. 42, 71-065 Szczecin, Poland
Novel biocompatible compounds that stabilize proteins in solution are in demand for biomedical and/or biotechnological applications. Here, we evaluated the effect of six ionic liquids, containing mono- or dicholinium [Chol]1or2 cation and anions of charged amino acids such as lysine [Lys], arginine [Arg], aspartic acid [Asp], or glutamic acid [Glu], on the structure, thermal, and storage stability of the Rapana thomasiana hemocyanin (RtH). RtH is a protein with huge biomedicinal potential due to its therapeutic, drug carrier, and adjuvant properties. Overall, the ionic liquids (ILs) induce changes in the secondary structure of RtH. However, the structure near the Cu-active site seems unaltered and the oxygen-binding capacity of the protein is preserved. The ILs showed weak antibacterial activity when tested against three Gram-negative and three Gram-positive bacterial strains. On the contrary, [Chol][Arg] and [Chol][Lys] exhibited high anti-biofilm activity against E. coli 25213 and S. aureus 29213 strains. In addition, the two ILs were able to protect RtH from chemical and microbiological degradation. Maintained or enhanced thermal stability of RtH was observed in the presence of all ILs tested, except for RtH-[Chol]2[Glu].
