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Updated: Aug 8, 2026
12:05
Production of Disulfide-stabilized Transmembrane Peptide Complexes for Structural Studies
Published on: March 6, 2013
Nonnative intermediate state of acid-stable beta-sheet protein
J J Yang1, A R Carroll, W Yang
1Department of Chemistry and Center for Drug Design, Georgia State University, Atlanta 30303, USA. chejjy@panther.gsu.edu
Cell Biochemistry and Biophysics
|April 28, 2001
Summary
The N-terminal domain 1 of CD2 (CD2-1) maintains its structure across a wide pH range but unfolds in TFE, revealing insights into protein folding and cell adhesion.
Area of Science:
- Protein structure and function
- Immunology
- Biochemistry
Background:
- CD2 is a cell adhesion molecule from the immunoglobulin superfamily, vital for immune cell interactions.
- It plays a key role in cell-cell adhesion through its Ig-like domains.
Purpose of the Study:
- To investigate the structural stability of the N-terminal domain 1 of CD2 (CD2-1) under varying pH and chemical conditions.
- To elucidate the factors contributing to the Ig beta-structure of CD2-1.
Main Methods:
- Near- and far-UV circular dichroism (CD) spectroscopy
- Fluorescence spectroscopy
- 1H nuclear magnetic resonance (NMR) spectroscopy
Main Results:
- CD2-1 retains its native tertiary structure from pH 1.0 to 10.0.
- 2,2,2-trifluoroethanol (TFE) disrupts tertiary structure and induces an alpha-helical conformation, correlating with inherent primary sequence helicity.
- Electrostatic interactions are less critical for native structure but vital for adhesion function; hydrophobic and hydrogen-bonding disruptions significantly alter conformation.
Conclusions:
- CD2-1's native structure is robust across a broad pH range.
- Hydrophobic interactions and hydrogen bonds are critical for maintaining CD2-1's conformation.
- Conformational flexibility in CD2-1 residues may facilitate domain-swapping and dimer formation.
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