On the Weak Binding and Spectroscopic Signature of SARS-CoV-2 nsp14 Interaction with RNA.

The SARS-CoV-2 non-structural protein 14 (nsp14), known as exoribonuclease is encoded from the large polyprotein of viral genome and is a major constituent of the transcription replication complex (TRC) machinery of the viral RNA synthesis. This protein is highly conserved among the coronaviruses and is a potential target for the development of a therapeutic drug. Here, we report the SARS-CoV-2 nsp14 expression, show its structural characterization, and ss-RNA exonuclease activity through vibrational and electronic spectroscopies.

Molecular insights on CALX-CBD12 interdomain dynamics from MD simulations, RDCs, and SAXS.

Na/Ca exchangers (NCXs) are secondary active transporters that couple the translocation of Na with the transport of Ca in the opposite direction. The exchanger is an essential Ca extrusion mechanism in excitable cells. It consists of a transmembrane domain and a large intracellular loop that contains two Ca-binding domains, CBD1 and CBD2.

CALX-CBD1 Ca-Binding Cooperativity Studied by NMR Spectroscopy and ITC with Bayesian Statistics.

The Na/Ca exchanger of Drosophila melanogaster, CALX, is the main Ca-extrusion mechanism in olfactory sensory neurons and photoreceptor cells. Na/Ca exchangers have two Ca sensor domains, CBD1 and CBD2. In contrast to the mammalian homologs, CALX is inhibited by Ca binding to CALX-CBD1, whereas CALX-CBD2 does not bind Ca at physiological concentrations.

Application of 2D BN/SDS-PAGE coupled with mass spectrometry for identification of VDAC-associated protein complexes related to mitochondrial binding sites for type I brain hexokinase.

Two types of binding sites for hexokinase, designated as Type A or Type B sites, have been shown to coexist on brain mitochondria. The ratio of these sites varies between species. HK1 attaches by reversibly binding to the voltage dependent anion channel (VDAC).