Research Briefing

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.

The beneficial rhizobacterium Bacillus velezensis SQR9 secretes YukE by the type VII secretion system; YukE inserts into the plant root cell membrane to cause iron leakage, which benefits SQR9 and thus promotes its rhizosphere colonization.

Mutational analysis of Akkermansia muciniphila identified genes important for growth in mucin and gut colonization. Mucin-degrading capabilities are essential for the bacterium to compete with other members of the microbiota, and mucin metabolism by A. muciniphila resulted in reduced transcription of genes involved with cholesterol biosynthesis in the host gut.

We characterized the cell-free DNA of bacteria and bacteriophages circulating in blood plasma of two cohorts of individuals with sepsis and uninfected controls. We found that the circulating phageome enables the identification of the bacterial pathogen with species-level resolution.

A set of genes, including a lectin, two scavenger receptors and two actin regulators, were found to aid the early steps of coral–algal endosymbiosis, including algae recognition and uptake, in a Xenia soft coral species. The findings were made possible by using a combination of RNA interference-mediated gene knockdown, single-cell RNA sequencing (scRNA-seq), bioinformatics and cell biology approaches.

Colistin-resistant bacteria require fatty acid synthesis to maintain cell envelope homeostasis; disrupting fatty acid biosynthesis leads to the remodelling of phospholipid composition and decreases the fluidity of the cell envelope. Inhibitors of fatty acid biosynthesis resensitize bacteria to colistin, allowing for the treatment of colistin-resistant bacterial infections in mice.

Breakthroughs in developing an effective human immunodeficiency virus (HIV) vaccine have been rare despite decades of effort. By combining vaccination with a topical microbicide that also potentiates vaccine-induced immunity, 16 out of 20 female macaques were protected against vaginal acquisition of the highly pathogenic simian immunodeficiency virus (SIV).

Previous studies have suggested the presence of a ‘blood microbiome’. Here, we analysed sequencing data generated from the blood of 9,770 healthy individuals and found no evidence for a common blood microbiome in these individuals.