Building protein backbones from C alpha coordinates.

Y Luo; X Jiang; L Lai; C Qu; X Xu; Y Tang

doi:10.1093/protein/5.2.147

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Building protein backbones from C alpha coordinates.

Y Luo·X Jiang·L Lai·C Qu·X Xu·Y Tang

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Abstract

An automatic procedure for building polyalanine backbones from guiding alpha-carbon positions is presented. Polyalanine backbones are built based on the geometric restraints of angle N-C alpha-C and the knowledge of main-chain dihedral angle distributions. A building module constructs a list of polyalanine backbones that follow exactly the C alpha trace. Then a selection module selects one backbone with the largest portion of phi-psi pairs in favoured regions. Several test cases on C alpha coordinates from X-ray refined structures give acceptable results. Less than 10% of the peptide planes are incorrectly built, and the result is not sensitive to random shift up to 0.5 A of C alpha coordinates.

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Amino Acid Sequence Enzymes Mathematical Computing Models, Molecular Molecular Sequence Data Molecular Structure Peptides Protein Conformation Proteins Software Journal Article

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Y Luo, X Jiang, L Lai, C Qu, X Xu, Y Tang. 1992. Building protein backbones from C alpha coordinates.. https://doi.org/10.1093/protein%2F5.2.147

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