Albany 2001

category image Biomolecular
SUNY at Albany
June 19-23, 2001

Protein structure and folding, a new start

In a globular protein the polypeptide chain returns to itself many times, making numerous chain-to-chain contacts - closed loops. This simple view of the protein structure, inexplicable, has never been considered. A statistical analysis of the sizes and locations of the closed loops in all major protein folds revealed that the loops have an almost-standard contour lengths of 25-30 amino acid residues and follow one after another along the chain [1]. The loop closure is maintained primarily by van der Waals interactions. A specific way to identify the tightest contacts of prime importance for the stability of a given crystallized protein is suggested and the notion of the van der Waals locks is introduced [2]. The loops closed by the van der Waals interactions provide a principally novel view of protein globule organization: the loop-n-lock structure. This opens a new perspective in understanding protein folding as well: the consecutive looping of the polypeptide chain and the locking of the loop ends by tight van der Waals interactions.

References and Footnotes

  1. Berezovsky, I.N., Grosberg, A.Y. & Trifonov, E.N. 2000. Closed loops of nearly standard size: common basic element of protein structure. FEBS Letters 466, 283-286.
  2. Berezovsky, I.N. & Trifonov, E.N. 2001. Van der Waals locks: loop-n-lock structure of globular proteins. J. Mol. Biol., in press.

Igor N. Berezovsky* and Edward N. Trifonov

Department of Structural Biology, The Weizmann Institute of Science, P.O.B. 26, Rehovot 76100, Israel
*Corresponding author: Dr. I.N. Berezovsky:
E-mail: Igor.Berezovsky@weizmann.ac.il Telefax: 972-8-9342653 Telephone: 972-8-9343367