Biology subjects

Guzenko, D.

Publications and source records attributed to Guzenko, D..

3 recordsLinked to original sources

bioRxiv2018

Optimal data-driven parameterization of coiled coils

-helical coiled coils (CCs) represent an important, highly regular protein folding motif. To date, many thousands of CC structures have been determined experimentally. Their geometry is usually modelled by theoretical equations introduced by F. Crick that involve a predefined set of parameters. Here we have addressed the problem of efficient CC parameterization from scratch by performing a statistical evaluation of all available CC structures. The procedure is based on the principal component analysis and yields a minimal set of independent parameters that provide for the reconstruction of the complete CC structure at a required precision. The approach is successfully validated on a set of canonical parallel CC dimers. Its applications include all cases where an efficient sampling of the CC geometry is important, such as for solving the phase problem in crystallography.

bioinformatics↗

bioRxiv2018

Z-score to evaluate the absolute quality of macromolecular models based on SAXS data

Small-angle X-ray scattering (SAXS) is a highly popular technique to assess the native three-dimensional structure of biological macromolecules in solution. Here we introduce a statistical criterion, Z-score, as a novel quality measure of SAXS-based structural models which positively correlates with data quality. We propose that, besides a goodness-of-fit (GOF) measure such as reduced {chi}2, the Z-score reflecting the ability of a given SAXS curve to differentiate between possible models should always be reported.

bioinformatics↗

bioRxiv2017

CCFold: Rapid And Accurate Prediction Of Coiled-Coil Structures And Application To Modelling Intermediate Filaments

Accurate molecular structure of the protein dimer representing the elementary building block of intermediate filaments (IFs) is essential towards the understanding of the filament assembly, rationalizing their mechanical properties and explaining the effect of disease-related IF mutations. The dimer contains a [~]300-residue long -helical coiled coil which is not assessable to either direct experimental structure determination or modelling using standard approaches. At the same time, coiled coils are well-represented in structural databases. Here we present CCFold, a generally applicable threading-based algorithm which produces coiled-coil models from protein sequence only. The algorithm is based on a statistical analysis of experimentally determined structures and can handle any hydrophobic repeat patterns in addition to the most common heptads. We demonstrate that CCFold outperforms general-purpose computational folding in terms of accuracy, while being faster by orders of magnitude. By combining the CCFold algorithm and Rosetta folding we generate representative dimer models for all IF protein classes. The source code is freely available at https://github.com/biocryst/IF

bioinformatics↗