Search

Bamboo-chicken farming (BCF), in which chickens are farmed in bamboo forests, is a common land-use type in China. However, little is known regarding the responses of soil bacterial communities to the introduction of BCF. In this study, we investigated and compared the bacterial communities in chicken gut, bulk soil, the rhizosphere, and roots, along with relevant soil properties, in a BCF area and a control area (a pure lei bamboo (Phyllostachys praecox) forest: PBF). The results showed that BCF significantly increased (p < 0.05) soil pH, organic carbon (SOC), total N, total P, alkali-hydrolysable N (AN), available K (AK), and available phosphorus (AP) and significantly decreased (p < 0.05) the soil C:N and C:P stoichiometry. BCF significantly altered the bacterial communities in soil and bamboo root systems. Bacterial composition changes associated with BCF were mostly related to C and N cycling, plant growth, and abiotic stress adaptation, such as an increase of Bacteroidetes, Flavobacterium , and Sphingomonas in bulk soil; Mizugakiibacter and Sphingomonas in rhizosphere soil; and Flavobacterium , Rhizobium , and Rhodomicrobium in root endophytes. A redundancy analysis (RDA) showed that all bacterial communities were significantly correlated with soil AN, AP, and TP, suggesting that N and P were the driving factors for bacterial composition and C cycle changes. The shared operational taxonomic units in the chicken gut–soil–bamboo root continuum indicated the microbial linkage among these components. Our results suggest that the microbial community and soil stoichiometry changes induced by chicken farming would alter bamboo ecosystem functions; the decreased overall stoichiometry and reduced bacterial richness (Chao 1 index) may indicate a high risk of nutrient and biodiversity loss. • Effects of bamboo-chicken farming (BCF) on soil were tested and evaluated. • BCF significantly increases soil nutrients but decreases C:N:P stoichiometry. • BCF markedly influences root-associated microbiomes. • Bacterial communities associated with chickens, soil, and bamboo roots are related. • BCF systems pose high risks for soil nutrient balance and biodiversity conservation. [ABSTRACT FROM AUTHOR]

NADPH oxidase (NOX) is a membrane-bound enzyme complex that generates reactive oxygen species (ROS). Mutations in NOX subunit genes have been implicated in the pathogenesis of inflammatory bowel disease (IBD), indicating a crucial role for ROS in regulating host immune responses. In this study, we utilize genetically deficient mice to investigate whether defects in p40 phox , one subunit of NOX, impair host immune response in the intestine and aggravate disease in an infection-based (Citrobacter rodentium) model of colitis. We show that p40 phox deficiency does not increase susceptibility of mice to C. rodentium infection, as no differences in body weight loss, bacterial clearance, colonic pathology, cytokine production, or immune cell recruitment were observed between p40 phox -/- and wild-type mice. Interestingly, higher IL-10 levels were observed in the supernatants of MLN cells and splenocytes isolated from infected p40 phox -deficient mice. Further, a higher expression level of inducible nitric oxide synthase (iNOS) was also noted in mice lacking p40 phox . In contrast to wild-type mice, p40 phox -/- mice exhibited greater NO production after LPS or bacterial antigen re-stimulation. These results suggest that p40 phox -/- mice do not develop worsened colitis. While the precise mechanisms are unclear, it may involve the observed alteration in cytokine responses and enhancement in levels of iNOS and NO., (© 2021 The Authors. FEBS Open Bio published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)