title: Topological distortion and reorganized modular structure of gut microbial co-occurrence networks in inflammatory bowel disease.
abstract: The gut microbiome plays a key role in human health, and alterations of the normal gut flora are associated with a variety of distinct disease states. Yet, the natural dependencies between microbes in healthy and diseased individuals remain far from understood. Here we use a network-based approach to characterize microbial co-occurrence in individuals with inflammatory bowel disease (IBD) and healthy (non-IBD control) individuals. We find that microbial networks in patients with IBD differ in both global structure and local connectivity patterns. While a "core" microbiome is preserved, network topology of other densely interconnected microbe modules is distorted, with potent inflammation-mediating organisms assuming roles as integrative and highly connected inter-modular hubs. We show that while both networks display a rich-club organization, in which a small set of microbes commonly co-occur, the healthy network is more easily disrupted by elimination of a small number of key species. Further investigation of network alterations in disease might offer mechanistic insights into the specific pathogens responsible for microbiome-mediated inflammation in IBD.
authors.affiliation: Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA.|Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Steven N
authors.initials: SN
authors.lastname: Baldassano
authors.affiliation: Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA.|Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA.|Department of Electrical &Systems Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Danielle S
authors.initials: DS
authors.lastname: Bassett
mesh_terms: D000069196:Gastrointestinal Microbiome; D041981:Gastrointestinal Tract / Q000382:microbiology*; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000382:microbiology* / Q000473:pathology*