Transmembrane conformation of the envelope protein of an alpha coronavirus, NL63.
Protein Sci
; 33(4): e4923, 2024 Apr.
Article
em En
| MEDLINE
| ID: mdl-38501465
ABSTRACT
The envelope (E) proteins of coronaviruses (CoVs) form cation-conducting channels that are associated with the pathogenicity of these viruses. To date, high-resolution structural information about these viroporins is limited to the SARS-CoV E protein. To broaden our structural knowledge of other members of this family of viroporins, we now investigate the conformation of the E protein of the human coronavirus (hCoV), NL63. Using two- and three-dimensional magic-angle-spinning NMR, we have measured 13 C and 15 N chemical shifts of the transmembrane domain of E (ETM), which yielded backbone (Ï, ψ) torsion angles. We further measured the water accessibility of NL63 ETM at neutral pH versus acidic pH in the presence of Ca2+ ions. These data show that NL63 ETM adopts a regular α-helical conformation that is unaffected by pH and the N-terminal ectodomain. Interestingly, the water accessibility of NL63 ETM increases only modestly at acidic pH in the presence of Ca2+ compared to neutral pH, in contrast to SARS ETM, which becomes much more hydrated at acidic pH. This difference suggests a structural basis for the weaker channel conductance of α-CoV compared to ß-CoV E proteins. The weaker E channel activity may in turn contribute to the reduced virulence of hCoV-NL63 compared to SARS-CoV viruses.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Infecções por Coronavirus
/
Coronavirus
Limite:
Humans
Idioma:
En
Revista:
Protein Sci
Assunto da revista:
BIOQUIMICA
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Estados Unidos