Dietary fat intake and shifts in gut bacterial community composition are associated with the development of obesity. To date, characterization of microbiota in lean versus obese subjects has been dominated by studies of gut bacteria. Fungi, recently shown to affect gut inflammation, have received little study for their role in obesity. We sought to determine the effects of high-fat diet on fungal and bacterial community structures in a mouse model using the internal transcribed spacer region 2 (ITS2) of fungal ribosomal DNA (rDNA) and the 16S rRNA genes of bacteria. Mice fed a high-fat diet had significantly different abundances of 19 bacterial and 6 fungal taxa than did mice fed standard chow, with high-fat diet causing similar magnitudes of change in overall fungal and bacterial microbiome structures. We observed strong and complex diet-specific coabundance relationships between intra- and interkingdom microbial pairs and dramatic reductions in the number of coabundance correlations in mice fed a high-fat diet compared to those fed standard chow. Furthermore, predicted microbiome functional modules related to metabolism were significantly less abundant in high-fat-diet-fed than in standard-chow-fed mice. These results suggest a role for fungi and interkingdom interactions in the association between gut microbiomes and obesity.
Bibliographical noteFunding Information:
We are grateful to Sara Gonia for technical assistance and helpful discussions during preparation of the manuscript. E.M. was supported by the Robert Tournut award of the French National Society of Gastroenterology. This work was further supported, in part, by NIH DK54733 and DK60521 to L.-N.W. and a Minnesota Viking Children's Research Fund award to C.A.G. Funding agencies had no role in study design, data collection and interpretation, or the decision to submit the work for publication. We declare that we have no competing financial interests. T.H. contributed to the design of the study, prepared DNA amplicons for sequencing, assisted with sequence and bioinformatic analyses, and wrote the manuscript. E.M., A.J., and G.A.-G. performed microbiome bioinformatic analyses and contributed to manuscript writing. Y.-W.L. performed all metabolic testing of animals, analyzed animal data, and edited the manuscript. L.-N.W. contributed to the conception and design of the study, analyzed the data, and edited the manuscript. D.K. contributed to the conception and design of the study, assisted with bioinformatic analyses, and edited the manuscript. C.A.G. contributed to the conception and design of the study, data analysis, and manuscript writing
© 2017 Heisel et al.
- Fungal-bacterial interactions
- High-fat diet