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ORF8a of SARS-CoV forms an ion channel: experiments and molecular dynamics simulations.

ABSTRACT: ORF8a protein is 39 residues long and contains a single transmembrane domain. The protein is synthesized using solid phase peptide synthesis and reconstituted into artificial lipid bilayers that forms cation-selective ion channels with a main conductance level of 8.9±0.8pS at elevated temperature (38.5°C). Computational modeling studies including multi nanosecond molecular dynamics simulations in a hydrated POPC lipid bilayer are done with a 22 amino acid transmembrane helix to predict a putative homooligomeric helical bundle model. A structural model of a pentameric bundle is proposed with cysteines, serines and threonines facing the pore.

SUBMITTER: Chen CC

PROVIDER: S-EPMC7094593 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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ORF8a of SARS-CoV forms an ion channel: experiments and molecular dynamics simulations.

Chen Cheng-Chang CC Krüger Jens J Sramala Issara I Hsu Hao-Jen HJ Henklein Peter P Chen Yi-Ming Arthur YM Fischer Wolfgang B WB

Biochimica et biophysica acta 20100812 2

ORF8a protein is 39 residues long and contains a single transmembrane domain. The protein is synthesized using solid phase peptide synthesis and reconstituted into artificial lipid bilayers that forms cation-selective ion channels with a main conductance level of 8.9±0.8pS at elevated temperature (38.5°C). Computational modeling studies including multi nanosecond molecular dynamics simulations in a hydrated POPC lipid bilayer are done with a 22 amino acid transmembrane helix to predict a putativ ...[more]

PMID: 20708597

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