2021 Summer Undergraduate Research Program (SURP) Symposium

Title

Enterococcus faecalis Colonization of the Helicoverpa zea Midgut Epithelium

Location

Ballroom, Maucker Student Union, University of Northern Iowa

Presentation Type

Poster Presentation (Electronic Copy Not Available)

Document Type

poster

Abstract

In recent years, there has been a surge in interdisciplinary efforts to elucidate the nutrient acquisition mechanisms that contribute to the success of a bacterium to not only survive in the gastrointestinal tract (G.I.) of Lepidopteran insects, but rather to thrive in it. However, bacterial colonization of Lepidoptera, one of the largest insect orders containing over 180,000 species is, to this day, poorly understood. Most of the works describing intestinal colonization have employed methods that inoculate larvae with an excessive number of bacteria relative to their natural abundance in the G.I. tract and/or disregarded key principles laid forth in Freter’s nutrient niche hypothesis which asserts that nutrient availability drives successful colonization. We developed a feeding bioassay using diet amended with rifampin to non-invasively introduce Enterococcus faecalis OG1RF into the Helicoverpa zea (corn earworm) G.I. tract in a single dose. We quantified E. faecalis populations using fecal plate counting. Preliminary results suggest that the continuous administration of artificial diet amended with 50 μg/mL rifampin opens a nutrient niche for E. faecalis to colonize at approximately 106 CFU/g frass (feces), whereas E. faecalis populations in solvent and negative control groups steadily declined. Collectively, this data supports a role for rifampin in suppressing susceptible endogenous bacteria and, subsequently, permitting stable colonization of E. faecalis OG1RF. Future works will continue optimizing this feeding protocol and characterize the role of metabolic pathways in colonization of isogenic E. faecalis mutants.

Start Date

30-7-2021 11:30 AM

End Date

30-7-2021 1:15 PM

Event Host

Summer Undergraduate Research Program, University of Northern Iowa

Faculty Advisor

Jerreme Jackson

Department

Department of Biology

File Format

application/pdf

Electronic copy is not available through UNI ScholarWorks.

Share

Import Event to Google Calendar

COinS
 
Jul 30th, 11:30 AM Jul 30th, 1:15 PM

Enterococcus faecalis Colonization of the Helicoverpa zea Midgut Epithelium

Ballroom, Maucker Student Union, University of Northern Iowa

In recent years, there has been a surge in interdisciplinary efforts to elucidate the nutrient acquisition mechanisms that contribute to the success of a bacterium to not only survive in the gastrointestinal tract (G.I.) of Lepidopteran insects, but rather to thrive in it. However, bacterial colonization of Lepidoptera, one of the largest insect orders containing over 180,000 species is, to this day, poorly understood. Most of the works describing intestinal colonization have employed methods that inoculate larvae with an excessive number of bacteria relative to their natural abundance in the G.I. tract and/or disregarded key principles laid forth in Freter’s nutrient niche hypothesis which asserts that nutrient availability drives successful colonization. We developed a feeding bioassay using diet amended with rifampin to non-invasively introduce Enterococcus faecalis OG1RF into the Helicoverpa zea (corn earworm) G.I. tract in a single dose. We quantified E. faecalis populations using fecal plate counting. Preliminary results suggest that the continuous administration of artificial diet amended with 50 μg/mL rifampin opens a nutrient niche for E. faecalis to colonize at approximately 106 CFU/g frass (feces), whereas E. faecalis populations in solvent and negative control groups steadily declined. Collectively, this data supports a role for rifampin in suppressing susceptible endogenous bacteria and, subsequently, permitting stable colonization of E. faecalis OG1RF. Future works will continue optimizing this feeding protocol and characterize the role of metabolic pathways in colonization of isogenic E. faecalis mutants.