- Title Information
- Title
- Differential Impacts of Hemin and Free Iron on Amoxicillin Susceptibility in Ex vivo Gut Microbial Communities
- Type of Resource (primo)
- dissertations
- Name:
Personal
- Name Part
- Pagano, Francesco
- Role
- Role Term:
Text
- creator
- Name:
Personal
- Name Part
- Belenky, Peter
- Role
- Role Term:
Text
- Advisor
- Name:
Personal
- Name Part
- Shukla, Anita
- Role
- Role Term:
Text
- Reader
- Name:
Personal
- Name Part
- Chellappa, Karthikeyani
- Role
- Role Term:
Text
- Reader
- Name:
Corporate
- Name Part
- Brown University. Biology and Medicine: Biotechnology
- Role
- Role Term:
Text
- sponsor
- Origin Information
- Copyright Date
- 2025
- Physical Description
- Extent
- x, 70 p.
- digitalOrigin
- born digital
- Note:
thesis
- Thesis (Sc. M.)--Brown University, 2025
- Genre (aat)
- theses
- Abstract
- Objective: The rise of antibiotic resistance infections worldwide has created a need to enhance the efficacy of existing antibiotics. Modification of metabolism has been shown to potentiate antibiotic lethality. In this study, we employed a novel ex vivo approach to culture microbial communities to study the effects of different forms of iron on amoxicillin susceptibility. Methods: Communities, ranging from known synthetic communities to complex unknown human stool microbiome samples, were cultured out and treated with amoxicillin and had their optical densities monitored. These samples were sequenced using an Oxford nanopore long read 16S rRNA V4-V9 approach and computationally defined using the Emu algorithm. The validity of this pipeline was confirmed along consortia, murine cecal content, and clinically relevant patient stool samples. Commercially available stool samples were then treated with between 0 and 75 M hemin, FeSO4, or FeCl3 for 24 hours alongside amoxicillin (0 – 10 g/mL) and profiled to identify the effects of different forms of iron on amoxicillin susceptibility. Results: Alpha diversity, beta diversity, and normalized relative abundances confirmed the efficacy of the selected ex vivo pipeline, allowing for ~ 77%% species retention over 24 hours. Treatment of communities with hemin protected Bacteroides, Escherichia-Shigella, Parabacteroides, and Parasutterella against amoxicillin. Two forms of free iron matched to this concentration did not protect these genera from amoxicillin. Conclusions: This study shows that the ex vivo protocol successfully generates large reproducible data for studying the effects of metabolic modulators on antibiotic susceptibility. Genera protected against killing through hemin supplementation are efficient in iron sequestration and produce large siderophore numbers. In the future, metatrascriptomics should be employed in future studies to identify common metabolic mechanisms of hemin-induced protection. This mechanistic understanding may lead to hemin-based therapies to modulate antibiotic efficacy in the host.
- Subject (fast)
(authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01019576")
- Topic
- Microbiology
- Subject (fast)
(authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/00810420")
- Topic
- Antibiotics
- Subject
- Topic
- gut microbiome
- Subject (fast)
(authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/00830894")
- Topic
- Beta lactam antibiotics
- Subject
- Topic
- dysbiosis
- Language
- Language Term (ISO639-2B)
- English
- Record Information
- Record Content Source (marcorg)
- RPB
- Record Creation Date
(encoding="iso8601")
- 20250707