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Socket2: A Program for Locating, Visualising, and Analysing Coiled-coil Interfaces in Protein Structures.

ABSTRACT:

Motivation

Protein-protein interactions are central to all biological processes. One frequently observed mode of such interactions is the α-helical coiled coil (CC). Thus, an ability to extract, visualise, and analyse CC interfaces quickly and without expert guidance would facilitate a wide range of biological research. In 2001, we reported Socket, which locates and characterises CCs in protein structures based on the knobs-into-holes (KIH) packing between helices in CCs. Since then, studies of natural and de novo designed CCs have boomed, and the number of CCs in the RCSB PDB has increased rapidly. Therefore, we have updated Socket and made it accessible to expert and non-expert users alike.

Results

The original Socket only classified CCs with up to 6 helices. Here, we report Socket2, which rectifies this oversight to identify CCs with any number of helices, and KIH interfaces with any of the 20 proteinogenic residues or incorporating non-natural amino acids. In addition, we have developed a new and easy-to-use web server with additional features. These include the use of NGL Viewer for instantly visualising CCs, and tabs for viewing the sequence repeats, helix-packing angles, and core-packing geometries of CCs identified and calculated by Socket2.

Availability and implementation

Socket2 has been tested on all modern browsers. It can be accessed freely at http://coiledcoils.chm.bris.ac.uk/socket2/home.html. The source code is distributed using an MIT license and available to download under the Downloads tab of the Socket2 home page.

SUBMITTER: Kumar P

PROVIDER: S-EPMC8652024 | biostudies-literature |

REPOSITORIES: biostudies-literature

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