Supramolecularity creates nonstandard protein ligands

• Authors: Barbara Piekarska , Janina Rybarska , Barbara Stopa , Grzegorz Zemanek , Marcin Król , Irena Roterman , Leszek Konieczny
• Languages of publication: EN

Abstracts

EN

Congo red and a group of structurally related dyes long used to stain amyloid proteins are known to associate in water solutions. The self-association of some dyes belonging to this group appears particularly strong. In water solutions their molecules are arranged in ribbon-like micellar forms with liquid crystalline properties. These compounds have recently been found to form complexeswith some native proteins in a non-standard way. Gaps formed by the local distribution of β-sheets in proteins probably represent the receptor sites for these dye ligands. They may result from higher structural instability in unfolding conditions, but also may appear as long range cooperative fluctuations generated by ligand binding. Immunoglobulins G were chosen as model binding proteins to check the mechanism of binding of these dyes. The sites of structural changes generated by antigen binding in antibodies, believed to act as a signal propagated to distant parts of the molecule, were assumed to be suitable sites for the complexation of liquid-crystalline dyes. This assumption was confirmed by proving that antibodies engaged in immune complexation really do bind these dyes; as expected, this binding affects their function by significantly enhancing antigen binding and simultaneously inhibiting C1q attachment. Binding of these supramolecular dyes by some other native proteins including serpins and their natural complexes was also shown. The strict dependence of the ligation properties on strong self-assembling and the particular arrangement of dye molecules indicate that supramolecularity is the feature that creates non-standard protein ligands, with potential uses in medicine and experimental science.

Keywords

EN

immunological signal; supramolecularity; Congo red; IgG

• Publisher: Polish Biochemical Society
• Journal: Acta Biochimica Polonica
• Year: 1999
• Volume: 46
• Issue: 4
• Pages: 841-851

Dates

published

1999

received

1999-06-21

revised

1999-10-01

accepted

1999-10-20

Contributors

author

Barbara Piekarska

• Institute of Biochemistry Collegium Medicum, Jagiellonian University, M. Kopernika 7, 31-034 Kraków, Poland

author

Janina Rybarska

• Institute of Biochemistry Collegium Medicum, Jagiellonian University, M. Kopernika 7, 31-034 Kraków, Poland

author

Barbara Stopa

• Institute of Biochemistry Collegium Medicum, Jagiellonian University, M. Kopernika 7, 31-034 Kraków, Poland

author

Grzegorz Zemanek

• Institute of Biochemistry Collegium Medicum, Jagiellonian University, M. Kopernika 7, 31-034 Kraków, Poland

author

Marcin Król

• Department of Biostatistics and Medical Informatics, Collegium Medicum, Jagiellonian University, M. Kopernika 17, 31-501 Kraków, Poland

author

Irena Roterman

• Department of Biostatistics and Medical Informatics, Collegium Medicum, Jagiellonian University, M. Kopernika 17, 31-501 Kraków, Poland

author

Leszek Konieczny

• Institute of Biochemistry Collegium Medicum, Jagiellonian University, M. Kopernika 7, 31-034 Kraków, Poland