Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 4 de 4
Filter
1.
PLoS One ; 16(12): e0251834, 2021.
Article in English | MEDLINE | ID: covidwho-1556859

ABSTRACT

Structural characterization of the SARS-CoV-2 full length nsp1 protein will be an essential tool for developing new target-directed antiviral drugs against SARS-CoV-2 and for further understanding of intra- and intermolecular interactions of this protein. As a first step in the NMR studies of the protein, we report the 1H, 13C and 15N resonance backbone assignment as well as the Cß of the apo form of the full-lengthSARS-CoV-2 nsp1 including the folded domain together with the flaking N- and C- terminal intrinsically disordered fragments. The 19.8 kD protein was characterized by high-resolution NMR. Validation of assignment have been done by using two different mutants, H81P and K129E/D48E as well as by amino acid specific experiments. According to the obtained assignment, the secondary structure of the folded domain in solution was almost identical to its previously published X-ray structure as well as another published secondary structure obtained by NMR, but some discrepancies have been detected. In the solution SARS-CoV-2 nsp1 exhibited disordered, flexible N- and C-termini with different dynamic characteristics. The short peptide in the beginning of the disordered C-terminal domain adopted two different conformations distinguishable on the NMR time scale. We propose that the disordered and folded nsp1 domains are not fully independent units but are rather involved in intramolecular interactions. Studies of the structure and dynamics of the SARS-CoV-2 mutant in solution are on-going and will provide important insights into the molecular mechanisms underlying these interactions.


Subject(s)
Magnetic Resonance Spectroscopy/methods , SARS-CoV-2/metabolism , Viral Nonstructural Proteins/chemistry , Amino Acid Sequence , COVID-19/pathology , COVID-19/virology , Carbon-13 Magnetic Resonance Spectroscopy , Humans , Mutation , Nitrogen Isotopes/chemistry , Protein Structure, Secondary , Proton Magnetic Resonance Spectroscopy , SARS-CoV-2/isolation & purification , Viral Nonstructural Proteins/genetics , Viral Nonstructural Proteins/metabolism
2.
Molecules ; 26(11)2021 Jun 07.
Article in English | MEDLINE | ID: covidwho-1383891

ABSTRACT

This paper reports the synthesis of branched alkylene guanidines using microfluidic technologies. We describe the preparation of guanidine derivatives at lower temperatures, and with significantly less time than that required in the previously applicable method. Furthermore, the use of microfluidics allows the attainment of high-purity products with a low residual monomer content, which can expand the range of applications of this class of compounds. For all the samples obtained, the molecular-weight characteristics are calculated, based on which the optimal condensation conditions are established. Additionally, in this work, the antiviral activity of the alkylene guanidine salt against the SARS-CoV-2 virus is confirmed.


Subject(s)
Antiviral Agents/chemical synthesis , Antiviral Agents/pharmacology , Guanidines/chemical synthesis , Guanidines/pharmacology , Microfluidics/methods , SARS-CoV-2/drug effects , Animals , COVID-19 , Carbon-13 Magnetic Resonance Spectroscopy , Chlorocebus aethiops , Inhibitory Concentration 50 , Spectrometry, Mass, Electrospray Ionization , Vero Cells
3.
Biomol NMR Assign ; 14(2): 329-333, 2020 10.
Article in English | MEDLINE | ID: covidwho-774089

ABSTRACT

The ongoing pandemic caused by the Betacoronavirus SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus-2) demonstrates the urgent need of coordinated and rapid research towards inhibitors of the COVID-19 lung disease. The covid19-nmr consortium seeks to support drug development by providing publicly accessible NMR data on the viral RNA elements and proteins. The SARS-CoV-2 genome encodes for approximately 30 proteins, among them are the 16 so-called non-structural proteins (Nsps) of the replication/transcription complex. The 217-kDa large Nsp3 spans one polypeptide chain, but comprises multiple independent, yet functionally related domains including the viral papain-like protease. The Nsp3e sub-moiety contains a putative nucleic acid-binding domain (NAB) with so far unknown function and consensus target sequences, which are conceived to be both viral and host RNAs and DNAs, as well as protein-protein interactions. Its NMR-suitable size renders it an attractive object to study, both for understanding the SARS-CoV-2 architecture and drugability besides the classical virus' proteases. We here report the near-complete NMR backbone chemical shifts of the putative Nsp3e NAB that reveal the secondary structure and compactness of the domain, and provide a basis for NMR-based investigations towards understanding and interfering with RNA- and small-molecule-binding by Nsp3e.


Subject(s)
Betacoronavirus/metabolism , Carbon-13 Magnetic Resonance Spectroscopy , Nitrogen Isotopes/chemistry , Nucleic Acids/metabolism , Proton Magnetic Resonance Spectroscopy , Viral Nonstructural Proteins/chemistry , Protein Binding , Protein Domains , SARS-CoV-2
4.
Biomol NMR Assign ; 14(2): 339-346, 2020 10.
Article in English | MEDLINE | ID: covidwho-716391

ABSTRACT

The SARS-CoV-2 genome encodes for approximately 30 proteins. Within the international project COVID19-NMR, we distribute the spectroscopic analysis of the viral proteins and RNA. Here, we report NMR chemical shift assignments for the protein Nsp3b, a domain of Nsp3. The 217-kDa large Nsp3 protein contains multiple structurally independent, yet functionally related domains including the viral papain-like protease and Nsp3b, a macrodomain (MD). In general, the MDs of SARS-CoV and MERS-CoV were suggested to play a key role in viral replication by modulating the immune response of the host. The MDs are structurally conserved. They most likely remove ADP-ribose, a common posttranslational modification, from protein side chains. This de-ADP ribosylating function has potentially evolved to protect the virus from the anti-viral ADP-ribosylation catalyzed by poly-ADP-ribose polymerases (PARPs), which in turn are triggered by pathogen-associated sensing of the host immune system. This renders the SARS-CoV-2 Nsp3b a highly relevant drug target in the viral replication process. We here report the near-complete NMR backbone resonance assignment (1H, 13C, 15N) of the putative Nsp3b MD in its apo form and in complex with ADP-ribose. Furthermore, we derive the secondary structure of Nsp3b in solution. In addition, 15N-relaxation data suggest an ordered, rigid core of the MD structure. These data will provide a basis for NMR investigations targeted at obtaining small-molecule inhibitors interfering with the catalytic activity of Nsp3b.


Subject(s)
Adenosine Diphosphate Ribose/metabolism , Apoproteins/chemistry , Betacoronavirus/metabolism , Carbon-13 Magnetic Resonance Spectroscopy , Nitrogen Isotopes/chemistry , Proton Magnetic Resonance Spectroscopy , Viral Nonstructural Proteins/chemistry , Amino Acid Sequence , Apoproteins/metabolism , Protein Domains , Protein Structure, Secondary , SARS-CoV-2 , Viral Nonstructural Proteins/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL