Microbiology

Monocytes recruited to skin infection are not involved in bacterial clearance but instead regulate local angiogenesis and healing.

A bacterial antiviral defence system generates a cyclic tri-adenylate that binds to a TIR–SAVED effector, inducing formation of a superhelical structure with adjacent TIR domains organizing into an active site, allowing NAD⁺ degradation.

The nucleus-like compartment formed in bacteria during infection by jumbo phage 201phi2-1 is composed of the bacteriophage protein chimallin, which can self-assemble into closed compartments in vitro.

Using a combination of methods, the mechanism of the antibiotic teixobactin is revealed.

Overall, this study describes the molecular mechanism of a druggable pathway that recapitulates in cellular assays the immunomodulatory effects associated with Akkermansia muciniphila, a prominent member of the gut microbiota.

Cryptococcus neoformans secretes CPL1 protein, which induces alternative activation of macrophages via Toll-like receptor 4 in mice and is essential for fungal virulence.

Through structural analysis of the activation of bacterial STING, the molecular basis of STING filament formation and TIR effector domain activation in antiphage signalling is defined.

The cryo-electron microscopy structure of the filamentous hydrogen-dependent CO₂ reductase (HDCR) enzyme from Thermoanaerobacter kivui, together with enzymatic analysis and in situ cryo-electron tomography, provides insight into the high catalytic activity of HDCR.

Within-host evolution is a critical regulator of commensal pathogenicity that provides a unique source of stochasticity in the development and progression of microbiota-driven disease.

Findings from a systematic antigenic analysis of these surging Omicron subvariants that this lineage of SARS-CoV-2 continues to evolve, successively yielding subvariants that are not only more transmissible but also more evasive to antibodies.

Enteric viruses replicate in salivary glands, can be propagated in salivary gland-derived spheroids and cell lines, and are released into saliva, which is a new transmission route having implications for therapeutics, diagnostics and sanitation measures.  

Global ocean microbiome survey reveals the bacterial family ‘Candidatus Eudoremicrobiaceae’, which includes some of the most biosynthetically diverse microorganisms in the ocean environment.

Cryo-electron microscopy structures of a 2.8 megadalton bacterial type IV secretion system encoded by the plasmid R388 and comprising 92 polypeptides provide insights into the stepwise mechanism of pilus assembly.

Biochemical and structural studies of the interactions between antibodies and spike proteins from SARS-CoV-2 Omicron subvariants indicate how these variants have evolved to escape antibody-mediated neutralization.

Combination therapy of broadly neutralizing monoclonal antibodies can provide long-term virological suppression in individuals infected with HIV without antiretroviral therapy.

A computational system termed MetaWIBELE (workflow to identify novel bioactive elements in the microbiome) is used to identify microbial gene products that are potentially bioactive and have a functional role in the pathogenesis of inflammatory bowel disease.

A fez gene cluster drives formation of ferrosomes, a distinct lipid-bounded organelle for iron storage, in diverse bacterial species.

Infection with Omicron after vaccination produces cross-neutralizing antibodies to other variants of concern, whereas this induces a limited response to non-Omicron variants in unvaccinated individuals.

Cryo-electron microscopy structures of the bile acid transporter NTCP in the apo state and in complex with the preS1 domain of hepatitis B virus (HBV) provide insight into NTCP substrate transport and HBV recognition mechanisms.

Isolates of authentic SARS-CoV-2 variants BA.1 and BA.2 exhibit similar infectivity and pathogenicity and show susceptibility to neutralizing therapeutic antibodies and antiviral compounds in mouse and hamster models.

Structural studies of human Na⁺–taurocholate co-transporting polypeptide in complex with nanobodies reveal mechanisms for bile salts transport and HBV recognition involving an open-pore intermediate state.

Group A Streptococcus secretes a protease, SpeB, that directly cleaves and activates gasdermin A to induce pyroptosis of infected keratinocytes, demonstrating a role for gasdermin A in immune defence against invasive microorganisms.

A study quantifying the neutralization of severe acute respiratory syndrome coronavirus 2 variants in individuals infected with Omicron/BA.1 shows that vaccinated individuals previously infected with Omicron have enhanced protection against reinfection with current variants, \including Omicron/BA.2, while Omicron/BA.1 infected unvaccinated individuals have limited protection.

Herpesvirus microRNAs interfere directly with host cell microRNA processing, thereby disrupting mitochondrial architecture, evading intrinsic host defences and driving the switch from latent to lytic infection.

Changes in climate and land use will lead to species aggregating in new combinations at high elevations, in biodiversity hotspots and in areas of high human population density in Asia and Africa, driving the cross-species transmission of animal-associated viruses.

A new humanized mouse model for COVID-19 demonstrates SARS-CoV-2 infection and subsequent activation of inflammasomes in human macrophages as a critical driver of disease.

The host blood-type-associated ABO genotype affects the abundance of specific bacteria in the pig intestine.

A third dose of an mRNA vaccine against SARS-CoV-2 results in an expanded B cell repertoire that produces antibodies with increased potency and breadth.

Experiments in yeast show that introns have a role in inducing phenotypic heterogeneity and that intron-mediated regulation of ribosomal proteins confers a fitness advantage by enabling yeast populations to diversify under nutrient-scarce conditions.

In situ experiments have demonstrated chemotaxis of marine bacteria and archaea towards specific phytoplankton-derived dissolved organic matter, which leads to microscale partitioning of biogeochemical transformation in the ocean.

A clinical study shows that immunotherapy with anti-HIV-1 antibodies maintains prolonged viral suppression after anti-retroviral treatment is discontinued and affects the size and composition of the intact but not the defective proviral reservoir.

A study in which gut microbiomes of 8,208 individuals from 2,756 families were characterized and correlated to 241 host and environmental factors defines microbiome patterns shared across diverse diseases and shows that the microbiome is shaped largely by environment and cohabitation.

A study using a biochemical screen of 57 phages in two bacterial species identifies and characterizes proteins enabling phages to evade CBASS and Pycsar immune systems, and describes the mechanisms involved.

Two defence systems are identified in pandemic Vibrio cholerae that act both cooperatively and independently to eliminate invasive plasmids and bacteriophages.

Structural analysis of Clostridioides difficile RNA polymerase in complex with fidaxomicin combined with biochemical, genetic and bioinformatic analyses identifies a key residue that determines fidaxomicin sensitivity.

Cryo-electron microscopy structures of the bacterial O-antigen ligase WaaL, combined with genetics, biochemistry and molecular dynamics simulations, provide insight into the mechanism by which WaaL catalyses the biosynthesis of lipopolysaccharide.

Antibody-mediated SARS-CoV-2 uptake by monocytes and macrophages triggers inflammatory cell death that aborts the production of infectious virus but causes systemic inflammation that contributes to COVID-19 pathogenesis.

N⁶-methyladenosine is enriched in poly(A) tails of VSG transcripts in Trypanosoma brucei, and when lacking result in mRNA degradation.

A small-molecule inhibitor of TMPRSS2 is effective against SARS-CoV-2 variants of concern in human lung cells and in donor-derived colonoids, and also shows prophylactic and therapeutic benefits in a mouse model of COVID-19.

A study reports the isolation and characterization of mouse-adapted SARS-CoV-2, demonstrates asapiprant to protect aged mice from its most severe effects, and identifies the PLA₂G2D–PGD₂/PTGDR pathway as a therapeutic target.

Bacterially produced bile acids inhibit T_H17 cell function, which may be relevant to the pathophysiology of inflammatory disorders such as inflammatory bowel disease.

Genetically diverse Candida albicans strains in patients with inflammatory bowel disease secrete a toxin and aggravate IL-1β-dependent intestinal inflammation.