Related Experiment Videos
Minimum structural requirement for an inhalational anesthetic binding site on a protein target
1Department of Anesthesiology, University of Pennsylvania Medical Center, Philadelphia, 19104-4283, USA.
Biochimica Et Biophysica Acta
|May 21, 1996
Summary
The anesthetic halothane specifically binds to long poly(L-lysine) chains, forming hydrophobic domains. This interaction depends on the polymer
Area of Science:
- Biochemistry
- Chemical Biology
- Polymer Science
Background:
- Inhalational anesthetics like halothane interact with biological molecules.
- Poly(L-lysine) is a model polypeptide with tunable properties.
Purpose of the Study:
- To investigate the interaction between halothane and poly(L-lysine) at different chain lengths and conformations.
- To elucidate the structural basis of halothane binding to polypeptides.
Main Methods:
- Direct photoaffinity labeling
- Fluorescence spectroscopy
- Circular dichroism (CD) spectroscopy
Main Results:
- Halothane specifically binds to long, uncharged alpha-helical poly(L-lysine) (≥300 residues).
- A stable stoichiometry of 1 halothane per 160 lysine residues was observed for long polymers.
- Binding was non-specific to short polymers or charged, random coil forms.
- CD spectroscopy indicated no significant disruption of poly(L-lysine) secondary structure by halothane.
Conclusions:
- Halothane binding is dependent on the supersecondary structure of poly(L-lysine), specifically helix-helix clustering.
- Confined hydrophobic domains within long polymers facilitate specific halothane interaction.
- Halothane does not extensively disrupt polypeptide hydrogen bonds.