Elucidating dynamic anaerobe metabolism with HRMAS C NMR and genome-scale modeling.

Anaerobic microbial metabolism drives critical functions within global ecosystems, host-microbiota interactions, and industrial applications, yet remains ill-defined. Here we advance a versatile approach to elaborate cellular metabolism in obligate anaerobes using the pathogen Clostridioides difficile, an amino acid and carbohydrate-fermenting Clostridia. High-resolution magic angle spinning nuclear magnetic resonance (NMR) spectroscopy of C.

Early Detection of Severe Acute Respiratory Syndrome Coronavirus 2 Variants Using Traveler-based Genomic Surveillance at 4 US Airports, September 2021-January 2022.

We enrolled arriving international air travelers in a severe acute respiratory syndrome coronavirus 2 genomic surveillance program. We used molecular testing of pooled nasal swabs and sequenced positive samples for sublineage. Traveler-based surveillance provided early-warning variant detection, reporting the first US Omicron BA.

In vivo commensal control of Clostridioides difficile virulence.

Leveraging systems biology approaches, we illustrate how metabolically distinct species of Clostridia protect against or worsen Clostridioides difficile infection in mice by modulating the pathogen's colonization, growth, and virulence to impact host survival. Gnotobiotic mice colonized with the amino acid fermenter Paraclostridium bifermentans survive infection with reduced disease severity, while mice colonized with the butyrate-producer, Clostridium sardiniense, succumb more rapidly. Systematic in vivo analyses revealed how each commensal alters the gut-nutrient environment to modulate the pathogen's metabolism, gene regulatory networks, and toxin production.

Predictive regulatory and metabolic network models for systems analysis of Clostridioides difficile.

We present predictive models for comprehensive systems analysis of Clostridioides difficile, the etiology of pseudomembranous colitis. By leveraging 151 published transcriptomes, we generated an EGRIN model that organizes 90% of C. difficile genes into a transcriptional regulatory network of 297 co-regulated modules, implicating genes in sporulation, carbohydrate transport, and metabolism.

Clostridioides difficile SinR' regulates toxin, sporulation and motility through protein-protein interaction with SinR.

Clostridioides difficile is a Gram-positive, anaerobic bacterium. It is known that C. difficile is one of the major causes of antibiotic associated diarrhea.

Pleiotropic roles of Clostridium difficile sin locus.

Clostridium difficile is the primary cause of nosocomial diarrhea and pseudomembranous colitis. It produces dormant spores, which serve as an infectious vehicle responsible for transmission of the disease and persistence of the organism in the environment. In Bacillus subtilis, the sin locus coding SinR (113 aa) and SinI (57 aa) is responsible for sporulation inhibition.

Effect of Mutation on Sporulation in the Epidemic Strain R20291.

is an important nosocomial pathogen and the leading cause of hospital-acquired diarrhea. Antibiotic use is the primary risk factor for the development of -associated disease because it disrupts normally protective gut flora and enables to colonize the colon. damages host tissue by secreting toxins and disseminates by forming spores.

Correction: Importance of Glutamate Dehydrogenase (GDH) in Clostridium difficile Colonization In Vivo.

[This corrects the article DOI: 10.1371/journal.pone.

Importance of Glutamate Dehydrogenase (GDH) in Clostridium difficile Colonization In Vivo.

Clostridium difficile is the principal cause of antibiotic-associated diarrhea. Major metabolic requirements for colonization and expansion of C. difficile after microbiota disturbance have not been fully determined.

Clostridium difficile glutamate dehydrogenase is a secreted enzyme that confers resistance to H2O2.

Clostridium difficile produces an NAD-specific glutamate dehydrogenase (GDH), which converts l-glutamate into α-ketoglutarate through an irreversible reaction. The enzyme GDH is detected in the stool samples of patients with C. difficile-associated disease and serves as one of the diagnostic tools to detect C.

Identification and characterization of Clostridium sordellii toxin gene regulator.

Toxigenic Clostridium sordellii causes uncommon but highly lethal infections in humans and animals. Recently, an increased incidence of C. sordellii infections has been reported in women undergoing obstetric interventions.