Mostly Microbes and Infection - by David Ojcius

Phylogeny strongly constrains glycoside hydrolase multidomain architecture across bacterial genera, while environmental factors fine‑tune domain organization in cosmopolitan lineages. Analysis of 158k GH proteins using domain‑adjacency networks reveals conserved lineage‑specific patterns and highlights accessory domains as key drivers of microbial functional adaptation.

A single‑patient study shows how repeat‑associated deletion of a blaNDM‑1 resistance module in Klebsiella pneumoniae produced divergent carbapenem phenotypes among otherwise closely related isolates. Stable genomes, a validated 10.5‑kb plasmid deletion, and growth differences highlight how structural plasmid variation can drive clinically relevant heteroresistance.

A study maps age‑related gut microbiome shifts and introduces MicroAge, a microbiome‑based aging clock. It identifies  Bifidobacterium   pseudocatenulatum as a geroprotective species depleted with age. In mice, supplementation restored intestinal balance, reduced systemic inflammaging, improved cognition and motor function, and extended healthspan. Its metabolite  5-aminovaleric acid betaine (5-AVAB)  reproduced many benefits.

Defined human Clostridia consortia 17‑mix and 11‑mix reverse established colitis in multiple murine IBD models. Beyond SCFA and IL‑10 pathways, these live biotherapeutic products suppress resident pathobionts and activate anti‑inflammatory AhR signaling via bacterial tryptophan metabolites, revealing IL‑10‑independent mechanisms of microbiome‑based therapy.

Gut microbiome diversity and composition differed across predefined age groups in a Taiwanese cohort. Several age‑associated genera showed partial agreement across complementary analytic methods. Adult gut microbiome profiles could predict chronological age, though only with modest accuracy, underscoring both biological signal and methodological limits.

Bacterial endosymbionts in Fusarium oxysporum enhance fungal virulence by reshaping the rhizosphere microbiome. Achromobacter spp. endosymbionts reduce disease‑suppressive bacteria, including Streptomyces, through beauvericin production. This tripartite interaction weakens microbiome‑based plant defense and intensifies pathogen impact.