Statistical properties of contact vectors.
We study the statistical properties of contact vectors, a construct to characterize a protein's structure. The contact vector of an N-residue protein is a list of N integers n(i), representing the number of residues in contact with residue i. We study analytically (at mean-field level) and numerically the amount of structural information contained in a contact vector. Analytical calculations reveal that a large variance in the contact numbers reduces the degeneracy of the mapping between contact vectors and structures. Exact enumeration for lengths up to N=16 on the three-dimensional cubic lattice indicates that the growth rate of number of contact vectors as a function of N is only 3% less than that for contact maps. In particular, for compact structures we present numerical evidence that, practically, each contact vector corresponds to only a handful of structures. We discuss how this information can be used for better structure prediction.
Kabakçioglu
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A
Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100, Israel.
Kanter
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I
Vendruscolo
M
M
Domany
E
E
D019295:Computational Biology / Q000379:methods / Q000706:statistics & numerical data; D008956:Models, Chemical; D015233:Models, Statistical; D010449:Peptide Mapping / Q000706:statistics & numerical data; D010455:Peptides / Q000737:chemistry; D017510:Protein Folding; D011506:Proteins / Q000737:chemistry*
D010455:Peptides; D011506:Proteins