Karen Pendergrass, Standards Team

Poststroke patients showed higher gut microbiota alpha diversity and a large shift in genus-level composition compared to healthy controls, correlating with functional recovery.

Metagenomic sequencing of pharyngeal swabs found 81 bacterial species enriched in COVID-19 patients, led by Streptococcus, Prevotella and Campylobacter, and two Streptococcus strains raised ACE2 expression in cells, hinting the throat microbiome may modulate SARS-CoV-2 infection.

A longitudinal mother-infant multi-omics study found large-scale transfer of mobile genetic elements shaping infant gut microbial assembly and metabolism.

Colorectal cancer patients with differing BMI show distinct gut microbial profiles that correspond with immune-related gene expression differences in tumor tissue.

Metagenomic analysis found COVID-19 respiratory samples harbored greater microbiome diversity than COPD or URTI samples, plus 16 unique non-SARS-CoV-2 viral genera.

In one-year-olds with moderate acute malnutrition, depleted Bacteroides fragilis and enriched oral commensals linked to altered plasma lipids, brain electrical activity, and vocalization.

Six weeks of endurance exercise shifted gut microbiome composition and function in previously sedentary adults, and raised fecal short-chain fatty acids in lean but not obese people. The changes largely reversed once exercise stopped.

Using a controlled in vitro gut model seeded with six donors, transit time alone explained 52% of microbial load and drove community shifts, with slower transit favoring fiber degraders like Akkermansia and boosting short-chain fatty acid output.

Among 64 patients with alcoholic cirrhosis in China's Pearl River Delta, those co-infected with the liver fluke Clonorchis sinensis had a distinct gut microbiota. Firmicutes and Prevotella marked the infected group, Enterococcus turned negatively linked to many genera, and the vancomycin-resistance pathway showed the strongest difference (p=0.0088).

In Peutz-Jeghers syndrome, intussusception was linked to a further drop in Faecalibacterium prausnitzii and enriched propanoate metabolism driven by expanded Escherichia coli.

A 12 week prebiotic improved cognition in older twins but did not speed chair rise time versus placebo.

Among 60 Malaysian men, waterpipe smokers showed a significantly altered salivary microbiome versus non-smokers, with Firmicutes elevated and Proteobacteria depleted, plus 37 shifted metabolic pathways favoring polymer degradation and amino acid metabolism.

Maternal balanced energy-protein supplementation in a Burkina Faso RCT reshaped the maternal gut microbiome, enriching Bacteroides fragilis and accelerating infant carbohydrate-metabolism gene pathways.

HIV-infected lactating women showed higher gut and systemic inflammation, with Slackia and Collinsella enriched and Clostridium sensu stricto 1 depleted.

Prevotella histicola is an immunomodulatory human commensal and a leading example of a medicine made from a microbe. It calms autoimmune inflammation, suppressing a multiple sclerosis model as effectively as interferon-beta and showing anti-inflammatory effects in early psoriasis and atopic dermatitis trials as the single-strain therapeutic EDP1815. Unlike its pro-inflammatory relative Prevotella copri, P. histicola is anti-inflammatory.

Saccharomyces boulardii is a probiotic yeast, a thermotolerant strain of Saccharomyces cerevisiae, used for decades against diarrheal illness. Because it is a eukaryote, antibacterial antibiotics do not kill it, which makes it uniquely suited to preventing antibiotic-associated diarrhea. Its strongest evidence is for antibiotic-associated and traveler's diarrhea, with emerging support for Clostridioides difficile recurrence.

Saccharomyces is a genus of yeasts, best known as brewer's and baker's yeast (Saccharomyces cerevisiae), that appear in the gut mycobiome largely as transient members from fermented foods. The genus is context-dependent: antibodies to it are a classic Crohn's disease marker, its mycobiome balance shifts in liver disease, and one member, Saccharomyces boulardii, is a widely used probiotic.

Enterococcus is a genus of hardy Gram-positive gut commensals, led by Enterococcus faecalis and the vancomycin-resistant Enterococcus faecium, that act as major opportunistic hospital pathogens. Enterococcal virulence depends on acquiring the metal manganese, which the host withholds through calprotectin.

Enterococcus faecium is a hardy gut commensal that has become a leading hospital pathogen and the E of the ESKAPE group, notorious for vancomycin resistance (VRE). It colonizes the gut and translocates to the bloodstream in vulnerable patients. Its virulence depends on acquiring the metal manganese, which the host withholds through calprotectin.

Enterobacter is a genus of Gram-negative Enterobacteriaceae, led by the Enterobacter cloacae complex, that live in the environment and gut and act as ESKAPE hospital pathogens. They carry an intrinsic AmpC beta-lactamase that drives cephalosporin resistance, and as enteric Enterobacteriaceae they share the family's nickel-dependent enzyme systems.

Viral infections are known to modulate the upper respiratory tract microbiome, but few studies have addressed differences in the nasopharyngeal microbiome following SARS-CoV-2 infection.

Actinomycetota, formerly called Actinobacteria, is one of the major bacterial phyla of the human gut. It is a broad, high-GC Gram-positive group whose gut role is led by the beneficial Bifidobacterium, especially in infancy, alongside context-dependent members such as Collinsella. As a phylum-level signal it reflects the balance of these very different organisms.

Hungatella is a genus of anaerobic gut Firmicutes, led by Hungatella hathewayi (formerly Clostridium hathewayi). Though a gut resident, it leans opportunistic: it has been linked to serious human infections and is consistently enriched in colorectal cancer and in sarcopenia, making it a disease-associated rather than beneficial taxon.

The skin microbiome is different in pediatric versus adult atopic dermatitis