Karen Peralta Martinez to Speak--Kohl Lab
Wednesday, September 28th, 2022
12:00pm
A219B Langley Hall
Title: Flexibility is key: The mammalian gut physiology and gut microbiota in response to diet
Abstract: Food provides the vital energy necessary to help animals and their resident microbes grow, maintain, and reproduce. How the gut, a multikingdom ecosystem, deals with environmental fluctuations is an essential question in the field of integrative biology. On the one hand, we are testing the effects of diet on animal physiology across different levels of biological organization. On the other hand, the field of microbial ecology is increasingly recognizing that isolating and culturing a diversity of microbes will be required to better understand the impact of gut microbes on animal physiology. The vertebrate gastrointestinal tract, however, is a flexible system that is highly responsive to internal and external dynamics. Phenotypic flexibility has been used to model expected changes in gut structure and function to better understand digestive efficiency under changing food supply. In a two-tier talk, I will share how in, project 1, we studied four closely related rodent species with different feeding strategies, Microtus montanus (herbivore), Peromyscus leucopus (omnivore), and Onychomys torridus (insectivore). We fed individuals with four different diets varying in nutrient content, and we observed unique responses in the mass and transcriptional responses of the cecum, the main site of bacteria fermentation of fiber, across our three species in response to different diets. Project 2 details how using a large rodent, the groundhog (Marmota monax), we processed and cultured gut content samples immediately following dissection and after being stored for three months at -80oC in one of five preservation methods to identify efficient methods for microbial culturability. While the effects of preservation methods are somewhat equivocal across growth treatments, we do find general trends with the Gut Microbiome Media, which mimics chemical conditions of the gut, yielding higher growth compared to other nutrient-type treatments. Understanding species differences in physiology and plasticity and improving the recovery of microbial diversity from field-collected samples will allow for a better understanding of wild host-associated microbiomes.