Download MendeleyAn Alanine-Zipper Structure Determined by Long Range Intermolecular Interactions
Liu, J., Lu, M.(2002) J Biol Chem 277: 48708-48713
- PubMed: 12368282
- DOI: https://doi.org/10.1074/jbc.M208773200
- Primary Citation of Related Structures:
1JCD - PubMed Abstract:
A major challenge in protein folding is to identify and quantify specific structural determinants that allow native proteins to acquire their unique folded structures. Here we report the engineering of a 52-residue protein (Ala-14) that contains exclusively alanine residues at the hydrophobic a and d positions of a natural heptad-repeat sequence. Ala-14 is unfolded under normal solution conditions yet forms a parallel three-stranded alpha-helical coiled coil in crystals. Ala-14 trimers in the solid state associate with each other through the pairing of polar side chains and formation of an extended network of water-mediated hydrogen bonds. In contrast to the classical view that local intramolecular tertiary interactions dictate the three-dimensional structure of small single-domain proteins, Ala-14 shows that long range intermolecular interactions can be essential in determining the metastable alanine-zipper structure. A similar interplay between short range local and longer range global forces may underlie the conformational properties of the growing class of natively unstructured proteins in biological processes.
Organizational Affiliation:
Department of Biochemistry, Weill Medical College of Cornell University, New York, New York 10021, USA.
