Anaerobic purinolytic enzymes enable dietary purine clearance by engineered gut bacteria.

Uric acid, the end product of purine degradation, causes hyperuricemia and gout, afflicting hundreds of millions of people. The debilitating effects of gout are exacerbated by dietary purine intake, and thus a potential therapeutic strategy is to enhance purine degradation in the gut microbiome. Aerobic purine degradation involves oxidative dearomatization of uric acid catalyzed by the O2-dependent uricase. The enzymes involved in purine degradation in strictly anaerobic bacteria remain unknown. Here we report the identification and characterization of these enzymes, which include four hydrolases belonging to different enzyme families, and a prenyl-flavin mononucleotide-dependent decarboxylase. Introduction of the first two hydrolases to Escherichia coli Nissle 1917 enabled its anaerobic growth on xanthine as the sole nitrogen source. Oral supplementation of these engineered probiotics ameliorated hyperuricemia in a Drosophila melanogaster model, including the formation of renal uric acid stones and a shortened lifespan, providing a route toward the development of purinolytic probiotics.

Interventions to Reduce Stress and Burnout among Teachers: A Scoping Review.

Background: Teaching is recognized as a highly challenging profession. Experience of chronic stress is a risk factor for poor mental and physical well-being, and burnout. There is limited knowledge regarding optimal interventions to address stress and burnout among teachers. Objective: To undertake a scoping review of the literature in the last five years to determine various psychological interventions to address stress and burnout among teachers. Method: The PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews was followed. Relevant search terms were used to determine different interventions adopted to reduce teachers' stress and burnout. Articles published between 2018 and 2022 were identified using five bibliographic databases. Relevant articles were extracted, reviewed, collated, and thematically analyzed, and findings s were summarized. Results: Forty studies conducted in Asia, North America, Oceania, Europe, and Africa, met the inclusion criteria. Sixteen kinds of burnout and stress-reduction interventions were identified. The most popularly studied intervention were Mindfulness-Based Interventions alone or in combination with yoga or Cognitive Behavioural Therapy (CBT), followed by Rational Emotive Behavioral Therapy (REBT). Mindfulness-Based Interventions led to decreased overall Teacher Stress Inventory (TSI) and emotional exhaustion subscale scores. REBT, primarily used with special education teachers, especially in Africa, has also shown positive results. Other interventions reporting positive outcomes include Inquiry-Based Stress Reduction (IBSR), the Stress Management and Resiliency Training Program (SMART), Cyclic Meditation, Group Sandplay, Progressive Muscle Relaxation, Autogenic Training, Sport-Based Physical Activity, Emotional Intelligence Ability Models and Christian Prayer and Prayer-Reflection. Conclusions: Stress and burnout can have a negative impact on teachers and, very often, on the students they teach. Implementing suitable school-based interventions is necessary to improve teachers' stress-coping ability, reduce the likelihood of burnout and improve general well-being. Policymakers, governments, school boards and administrators should prioritize the implementation of school-based awareness and intervention programs.