Middle East respiratory syndrome coronavirus (MERS-CoV) is a human pathogen responsible for a severe respiratory illness that emerged in 2012. Structural information about the proteins that constitute the viral particle is scarce. In order to contribute to a better understanding of the nucleoprotein (N) in charge of RNA genome encapsidation, the structure of the C-terminal domain of N from MERS-CoV obtained using single-crystal X-ray diffraction is reported here at 1.97 Å resolution. The molecule is present as a dimer in the crystal structure and this oligomerization state is confirmed in solution, as measured by additional methods including small-angle X-ray scattering measurements. Comparisons with the structures of the C-terminal domains of N from other coronaviruses reveals a high degree of structural conservation despite low sequence conservation, and differences in electrostatic potential at the surface of the protein.
Serological tests
are essential for the control and management
of COVID-19 pandemic (diagnostics and surveillance, and epidemiological
and immunity studies). We introduce a direct serological biosensor
assay employing proprietary technology based on plasmonics, which
offers rapid (<15 min) identification and quantification of severe
acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in
clinical samples, without signal amplification. The portable plasmonic
device employs a custom-designed multiantigen (RBD peptide and N protein)
sensor biochip and reaches detection limits in the low ng mL
–1
range employing polyclonal antibodies. It has also been implemented
employing the WHO-approved anti-SARS-CoV-2 immunoglobulin standard.
A clinical validation with COVID-19 positive and negative samples
(
n
= 120) demonstrates its excellent diagnostic sensitivity
(99%) and specificity (100%). This positions our biosensor as an accurate
and easy-to-use diagnostics tool for rapid and reliable COVID-19 serology
to be employed both at laboratory and decentralized settings for the
disease management and for the evaluation of immunological status
during vaccination or treatment.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.