Articles in 2020

In this manuscript, the authors address evolutionary questions on the emergence of SARS-CoV-2. They find that SARS-CoV-2 is not a recombinant of any sarbecoviruses detected to date, and that the bat and pangolin sequences most closely related to SARS-CoV-2 probably diverged several decades ago or possibly earlier from human SARS-CoV-2 samples.

This study reveals features of Epstein–Barr virus that are similar but not identical to the closely related Kaposi’s sarcoma-associated herpesvirus. The authors provide locations of protein components within the viral capsid and reveal different conformers of protein components by revealing variations in links between capsid proteins and exploiting approaches with relaxation of symmetry. The capsid-associated tegument complex is loaded on to the capsid with long-range asymmetry, relative to the location of the portal vertex (the site of genome entry and egress).

This study reveals that prion-like domains support the assembly of transcription factor complexes that control fungal cell identity and highlights parallels with the ‘super-enhancers’ that regulate mammalian cell fate.

Subinhibitory levels of sulfamethoxazole, an antibiotic used to treat Escherichia coli infections, trigger a previously undescribed metabolic pathway in E. coli that comprises a family of hybrid pterin–phenylpyruvate conjugates called colipterins. These metabolites are antioxidants, have immunomodulatory properties and improve colitis in a murine model.

A virus has been found inserted into the genome of the most abundant bacteria in the oceans. Even though the virus can kill its host, the genes carried by the prophage may help these bacteria flourish around the world.

A dual-mechanism compound with antibacterial activity that targets both folate metabolism and membrane integrity, with a favourable resistance profile in vitro, is identified by screening a small molecule library.

Marine bacteria that produce an enormous panoply of glycan-degrading enzymes are identified as having a role in releasing fixed carbon present in glycan-rich cell walls of brown algae.

We reflect on why we need the World Health Organization now more than ever.

Iron-scavenging molecules called siderophores that are produced by the native microbial residents of plant roots fend off plant pathogens such as Ralstonia solanacearum.

Here, the authors identify lymphocyte antigen 6E (LY6E) as a coronavirus (CoV) restriction factor that prevents infection of B cells and dendritic cells. LY6E inhibits both human and mouse CoV entry into cells by interfering with viral spike protein-mediated membrane fusion. It facilitates an antiviral immune response that prevents liver disease and reduces death in the mouse model of MHV-A59 CoV infection.

Metagenomic analysis of a single RNA virome from the Yangshan Deep-Water Harbour in China enabled the recovery of more than 4,500 distinct RNA viruses, doubling the known set of RNA viruses to date, and provided insights into their biology.

Vpu prevents HIV superinfection and immune activation by modulating DNA repair mechanisms, particularly by inhibiting homologous repair. Vpu achieves this by disrupting the RanBP2–RanGAP1*SUMO1–Ubc9 complex at the nuclear pore to reduce PML SUMOylation and consequent PML nuclear body formation, which hampers the homologous recombination factors Rad52 and BLM.

The AcP10 protein—an active uridine kinase, encoded by the beluga whale coronavirus SW1—is an antagonist of the integrated stress response that acts downstream of phosphorylation of the translation initiation factor eIF2, irrespective of which eIF2 kinase is activated. AcP10 acts as a competitive inhibitor of the eIF2[P]–eIF2B interaction by binding to eIF2B. A protein with a similar function is also encoded by Aichivirus, a picornavirus.

The authors propose a nomenclature of SARS-CoV-2 lineages to assist research on epidemiology and decision-making during the COVID-19 pandemic. This nomenclature is based on the SARS-CoV-2 phylogeny and designed to provide a real-time bird’s-eye view of the diversity of the hundreds of thousands of genome sequences collected worldwide. The authors develop a set of rules to produce a hierarchical four-level nomenclature of labels that is flexible and dynamic.

This study highlights a unique drug target for trypanosomatid parasitic protozoa and a new chemical tool for investigating the function of their divergent kinetochores.

In this Article, the authors report the discovery of a small molecule (GHP-88309) that is a new class of allosteric viral polymerase inhibitor that works against two different genera of paramyxoviruses.

Adenovirus produces two early proteins, E1B55K and E4orf6, that become components of the host cell ubiquitin ligase complex comprising elongin-B and C, cullin-5 and RBX1. The authors identified new protein substrates that are ubiquitinated by the E1B55K–E4orf6 complex and find that hnRNP-C and RALY play an inhibitory role on late viral RNA transcripts and that this is counteracted by ubiquitination due to a reduction on the capacity of these proteins to interact with viral RNA.

Bacteria-derived lactate mediates inhibition of HDAC11 during Staphylococcus aureus biofilm infections, resulting in epigenetic changes that reprogramme the host immune response.

This is a comparative analysis of the performance of the primer–probe sets from four open-source molecular diagnostic assays for SARS-CoV-2 recommended by the World Health Organization.