Mostly Microbes and Infection - by David Ojcius

Highlights • HCAs dominate meconium (>50%) as primary bile acids produced by fetal CYP3A7 • HCAs shape intestinal immune tolerance by promoting Treg cells and suppressing Th17 cells • High neonatal HCAs protect against gastrointestinal disorders and infections

Highlights • Respiratory growth with cysteine increases H 2 S production in U. maydis. • Endogenous H 2 S promotes mitochondrial biogenesis and metabolic remodeling . • H 2 S shifts respiration toward alternative oxidase-dependent electron transport . • Elevated H 2 S increases global protein S-sulfenylation and S-persulfidation. • Endogenous H 2 S modulates disease severity during maize infection.

Highlights • Epigenetic phase variations (ePVs) are prevalent in the human gut microbiome • Long- and short-read metagenomic data reveal ePVs associated with antibiotics and FMT • An ePV in an A. muciniphila strain regulates mucC , enhancing tolerance to amoxicillin • ePV creates intra-strain heterogeneity, enhancing bacterial adaptation via bet-hedging

Highlights • CRKP-derived outer membrane vesicles (OMVs) serve as multifunctional vectors for antibiotic resistance, encapsulating a diverse array of lipids and harboring the carbapenemase gene bla KPC . • Meropenem stress triggers a marked upregulation of membrane lipids in CRKP-OMVs, particularly sphingolipids (SP), glycerolipids (GL), glycerophospholipids (GP), and fatty acids (FA), which likely fortify bacterial antibiotic resistance through enhanced membrane stability and efflux efficiency. • CRKP-OMVs mediate horizontal gene transfer of bla KPC-2 to both intra- and interspecies susceptible bacteria, with meropenem-induced lipid remodeling significantly boosting transformation efficiency—a potential accelerator for environmental resistance spread.

Highlights • Incidence of CCPD rose to 9.04 per 100,000 population in the post-pandemic 2024. • Lower β-lactam susceptibility of the pneumococcal isolates is due to serotype shift. • Resistant non-PCV13 clones are emerging from clonal expansion and capsular switch.

Highlights • Organic acid-based DESs act against colistin- and methicillin-resistant strains. • T-glycoline–nanoparticle mix enhances activity against MRSA. • Organic DESs eliminate mature biofilms and damage bacterial cells. • T-glycoline and oxaline reduce titres of enveloped and non-enveloped viruses. • Nanoparticles enhance the safety of DESs.