Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most prevalent liver disease worldwide. The liver communicates with the intestine, in large part through the gut microbiota. Microbial enzymes are key mediators that affect the progression of MASLD and the more severe metabolic dysfunction-associated steatohepatitis (MASH). These enzymes contribute to the metabolism or biosynthesis

A new study published in Science1 reveals a crucial connection between our neonatal gut microbiota composition and the long-term health of our pancreas, specifically focusing on β-cell development and the subsequent lifelong impact microbe-induced β-cell expansion has on metabolic health, including prevention of, and even potential reversal of, diabetes.

What enables certain microbes to successfully colonize the mammalian gut? In a recent issue of Cell, Liu et al. present a microbial cross-species genomic framework that identifies conserved genetic determinants of gut residency. This study provides a roadmap for developing more effective microbiome-based therapeutics, advancing our understanding of host-microbe interactions.

Bacteria deploy many distinct mechanisms to resist protist predation in natural environments. In a recent study published in Cell, Zhang et al. discover a chemical radar used by the plant pathogen Pseudomonas syringae to sense and kill an amoeba predator.

The Western equine encephalitis virus (WEEV), an alphavirus causing severe neurological disease, exhibits fluctuating epidemic patterns and enigmatic host adaptability. Recent studies by Raju et al. and Fan et al. in Cell reveal glycoprotein modifications enabling receptor switching, explaining its reduced human pathogenicity while underscoring re-emergence risks.

Antiviral defense requires signal transmission that connects the perception of viral infection to activation of plant immunity. Findings in Nature by Huang et al. describe key players whereby RING1-IBR-RING2-type ubiquitin ligase (RBRL) recognizes viral coat proteins to release NINJA3-mediated suppression of jasmonate signaling and initiate broad-spectrum antiviral responses in rice.

Species-level uniformity on the skin surface masks substantial strain-level diversity modulated by ecological dynamics. In this issue of Cell Host & Microbe, Jacob et al. uncover dynamic intraspecies behaviors, revealing different patterns of colonization and persistence for two important skin commensals.

In this issue of Cell Host & Microbe, Feng et al. find that broad-spectrum antibiotics perturbed the ecology of the gut microbiome in individuals receiving a rabies vaccine, resulting in systemic inflammatory responses. Such inflammation is hypothesized to alter immune homeostasis with consequences for immunological responsiveness to vaccination.

(Cell Host & Microbe 32, 1365–1379.e1–e10; August 14, 2024)

Plant phenolic glycosides are thought to be beneficial for human health. In a recent issue of Cell, Kuziel et al. identified that Bacteroides species, the dominant symbiotic bacteria in the gut, harbor a unique multi-enzyme system that processes dietary plant glycosides into various aglycone metabolites with antimicrobial or immunomodulatory activities.

Three studies recently published in Cell reveal distinct ACE2 binding interactions across the merbecoviruses, uncovering how HKU5 can use ACE2s of many non-human hosts and identifying a novel HKU5 lineage capable of using human ACE2. These findings highlight merbecovirus receptor plasticity and caution for preparedness against potential merbecovirus threats.

Immunoglobulin A (IgA) antibodies maintain homeostasis between the host and its microbiota, by exerting luminal control over fungi and bacteria. In this issue of Cell Host & Microbe, Lisicka et al. show that IgA antibodies also control the population of specific members of our virome.

Plasmodium liver infection is limited by type I interferons (IFN-I) but the mechanisms remain unknown. In this issue of Cell Host & Microbe, Marques-da-Silva et al. reveal two IFN-I-induced pathways that trigger the fusion of lysosomes with, and the disruption of, the membranes surrounding the parasites, leading to their clearance.

In this issue of Cell Host & Microbe, Honda et al. identify an antiviral defense system in fungi. Mycoviruses trigger the expression of RNA-editing enzymes, which catalyze the editing of mRNAs encoding zinc finger transcription factors. This system differs from the RNA interference and is conserved in filamentous fungi.

Staphylococcus aureus is a major pathogen with rising antibiotic resistance. In this issue of Cell Host & Microbe, Shekhar et al. find that quinoxalinediones reduce S. aureus lung infections through α-hemolysin inhibition, offering a therapeutic strategy for S. aureus pneumonia.

The nose-to-brain pathway for drug delivery holds promising therapeutic outcomes. In a recent issue of Cell, Shen et al.1 successfully identified and characterized a commensal bacterial strain to enable the intranasal delivery of therapeutics, using obesity as a disease model.

Early-life antibiotic (ELA) exposure has garnered attention for its potential role in modulating obesity risk, although outcomes from mouse experiments and human epidemiological studies often vary based on dosage and sex. Low-dose (subtherapeutic) antibiotics can enhance energy availability through moderate alterations in gut microbiome profile, while high-dose (therapeutic) antibiotics substantially

In a recent article in Nature, Cook et al. demonstrate that an autoactive mutant of CNGC15 generates continuous low-frequency calcium (Ca2+) oscillations, enabling sustained flavonoid production and promoting endosymbiont attraction and root colonization. The mutant simultaneously enables endosymbiosis gene induction, even under high-nutrient conditions, offering avenues for improving crop-microbe

The mucosal immune response of the urinary bladder to bacterial infection is complex, as immune cells must efficiently neutralize and contain the infection while preventing harmful pathology. A recent Immunity paper by Li et al. illuminates the critical role of a resident macrophage subset in preventing invasive and life-threatening disease.

Studies on industrialized populations have uncovered gut microbiome diversity and its disease associations. However, non-industrialized populations remain underrepresented. In a recent paper, Maghini et al. present findings from the AWI-Gen 2 Microbiome Project, substantially expanding our knowledge of the African gut bacterial and viral diversity and its linkage with HIV infection.

Symbiotic relationships between mammalian hosts and their flora impact host immunity and disease. In this issue, Winsor and colleagues define a trans-kingdom interaction, which protects against colorectal cancer. Tritrichomonas protists initiate a Bacteroides bloom and sphingolipid release, which activates the NLRP6 inflammasome, enhancing protective mucus secretion by sentinel goblet cells.

Plant development can be drastically stimulated by beneficial microorganisms. However, the underlying mechanisms are not always understood. In this issue of Cell Host & Microbe, Castrillo et al. investigated this question and uncovered that leaf-associated bacteria can stimulate individual leaf development through their influence on the growth-defense trade-off.

Industrialization alters the gut microbiome, increasing chronic disease risk. In a recent study published in Cell, Li et al. show that a diet mimicking non-industrialized patterns (“Restore” diet) enhances Limosilactobacillus reuteri persistence and improves microbiome-derived metabolites, leading to cardiometabolic benefits and highlighting the potential of interventions aimed at restoring the gut

Two recent studies by Gribonika et al. and Bousbaine et al., published in Nature, describe the mechanisms underpinning skin autonomous B cell antibody responses to skin microbes and the immunodominant antibody target in Staphylococcus epidermidis that can be utilized to engineer novel topical vaccination strategies.

Symbiotic gut bacteria have evolved mechanisms to selectively recognize and colonize an appropriate host. In a recent issue of Science, Gutiérrez-García et al. reported a colonization island that encodes sugar-binding adhesins used by Lactiplantibacillus plantarum to colonize its symbiotic niche in the foregut of its host, Drosophila melanogaster.