Research Briefing

Fusarium oxysporum f. sp. cubense tropical race 4 is threatening worldwide banana production. This study revealed a distinct evolutionary origin of tropical race 4 and how accessory genes and nitrosative pressure may have provided potential weaponries used by the pathogen to infect banana plants.

Mobile genetic element fluorescence in situ hybridization (MGE-FISH) creates spatial maps of target genes in microbiomes. We combine MGE-FISH with high phylogenetic resolution FISH (HiPR-FISH) to simultaneously map bacterial taxa and mobile genetic elements such as plasmids and phage, identifying their host taxa and revealing mobile genetic element spatial distribution.

Toxoplasma gondii, a eukaryotic brain parasite that infects one in three people worldwide, was engineered to deliver therapeutics to neurons in the mouse brain. This technology opens the door to deliver multiple large proteins that have been undeliverable with previous approaches. Further development, such as vector attenuation, will be necessary for many applications.

Plasmid coupling creates heterogeneity in copy number and, therefore, expression across a microbial population. We demonstrate that plasmid-encoded fitness differences between individuals can then lead to adaptation of the population to specific environments and can promote both genetic stability and memory of past environmental exposures.

We characterized the evolution of measles antibody responses and drivers of individual variability, from birth and following vaccination. Our findings highlight the strong predictability of individual measles antibody evolution, as well as the long-term immunological consequences of sex and birth route.

The largest-ever study of alterations in the host’s microbiome and immune response during spaceflight shows shifts in the skin and oral microbiota during flight that are consistent across astronauts, with numerous changes in microbial gene expression that also correlate to host immune activity.

Our study investigated microbial dynamics involved in the relative enrichment of oral bacteria in faeces. Results in mice and from human patients indicated that high percentages of oral bacteria reflect a depleted gut microbiota, with oral bacteria simply passing through rather than expanding in the gut, which has implications for gastrointestinal disease treatment.

We characterize the activity of fluorofolin, a potent inhibitor of dihydrofolate reductase, against Pseudomonas aeruginosa. By exploiting a divergence in thymidine metabolism, fluorofolin becomes selective for P. aeruginosa in the presence of thymine, demonstrating that it can be a narrow-spectrum antibiotic for this bacterial pathogen.

Characterizing bacterial responses to mixtures of chemical pollutants reveals interactive effects among pollutants. Our study highlights the predictability and resilience of microbial responses to complex mixtures of pollutants, offering the potential for improvements in ecotoxicological assessments.

Human norovirus infection is a major global health concern, but a suitable animal model is lacking. We have established repeated infection with human norovirus in rhesus macaques via oral challenge. Animals demonstrate virus shedding in the stool and subsequent serum antibody responses, and virus replication is detected in the small intestine.

Cases of Buruli ulcer in southeastern Australia have increased over the past 10 years. Native possums are a reservoir for Mycobacterium ulcerans (the cause of Buruli ulcer), but the route of transmission to humans is unclear. Our findings identify mosquitoes as the vector of M. ulcerans from possums to humans.

The placenta nourishes the foetus and supports its development and growth. Our study now identifies the placenta as a potential route for foetal infection with Streptococcus agalactiae (group B Streptococcus), as indicated by an exaggerated in utero inflammatory response and poor perinatal outcome when group B Streptococcus is detected in the placenta.

Counting the number of viable cells in a culture remains a critical measurement in microbiology, but traditional dilution assays are time- and reagent-consuming. We developed the geometric viability assay that overcomes these limitations by leveraging microbial colony distribution in a cone — a pipette tip — to calculate viability across six orders of magnitude.

Empowering women through citizen science, from using self-collected vaginal samples to participant input on research questions, we decoded nuances in the composition of the vaginal microbiota — thereby linking female health and lifestyle to vaginal microbiota diversity. We crafted a unique dataset that should inspire new diagnostic and therapeutic opportunities.

Human skin organoids are susceptible to mpox virus infection and support infectious virus production. Treatment of infected skin organoids with the antiviral drug tecovirimat can inhibit infectious virus production and prevent host transcriptome rewiring. Thus, skin-organoid-based models are robust for studying mpox virus infection and testing therapeutics.

We used functional genomics to understand how hospital biocides impact the human pathogen Acinetobacter baumannii. Low concentrations of various biocides dissipated the membrane potential of A. baumannii, which we demonstrated could antagonize the potency of antibiotics.

Detection of poliovirus by cell culture and subsequent serotype identification via Sanger sequencing can be slow, delaying responses to emerging outbreaks. Direct virus detection using nested reverse transcription PCR and nanopore sequencing was prospectively validated in the Democratic Republic of the Congo and yielded accurate results in a fraction of the time.

Dietary fibre deprivation in mice increases the abundance of gut microbial mucin-degrading species, leads to barrier dysfunction and increases local type 2 inflammation. In a tractable human microbiota mouse model, the presence of Akkermansia muciniphila results in increased anti-commensal IgE and type 2 immune responses, worsening food allergy symptoms following sensitization.

Armillaria species, fungal pathogens prevalent in temperate forests, have acquired hundreds of genes from Ascomycota fungi through horizontal gene transfer. These genes have influenced Armillaria spp. pathogenicity and plant biomass degradation abilities and contribute to uncovering key insights into the evolutionary history and ecological effects of these fungi.

d-amino acids are known to have a variety of functions. An investigation into the roles of d-arginine and d-lysine shed light on the stress-dependent mechanism employed by Vibrio cholerae to escape from unfavourable niches and to shape complex ecological systems.