A Caltech Library Service

Microbial Modulation of Host Locomotion


Schretter, Catherine Elizabeth (2019) Microbial Modulation of Host Locomotion. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/Z1DX-4J03.


Coordinated locomotor behavior is critical for the survival and propagation of an individual and is modulated by internal and external sensory inputs. The microbiota regulates host metabolism, which is closely intertwined with motor behavior. However, little is known regarding influences by the gut microbiome on host locomotion, or the pathways involved. The work presented in this thesis examines microbial regulation of locomotor behavior from both bacterial and host perspectives. Removal of the microbiota results in hyperactivity in female D. melanogaster, which is reversible through colonization with specific bacteria or administration of bacterial-derived products, including xylose isomerase (Xi) from Lactobacillus brevis. We found that Xi modulates host speed via sugar metabolism and octopamine signaling in flies. Additionally, aspects of microbial regulation of host locomotion appear to be conserved in mice. This work suggests that microbial modulation of host physiology extends beyond local intestinal effects to locomotor behavior through alterations in energy-related pathways.

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:Microbiota; Locomotion; Behavior; Drosophila
Degree Grantor:California Institute of Technology
Division:Biology and Biological Engineering
Major Option:Biology
Awards:Everhart Distinguished Graduate Student Lecturer Award, 2016.
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Mazmanian, Sarkis K.
Thesis Committee:
  • Lester, Henry A. (chair)
  • Anderson, David J.
  • Gradinaru, Viviana
  • Mazmanian, Sarkis K.
Defense Date:14 August 2018
Funding AgencyGrant Number
NIH Training Grant5T32 GM07616
Center for Environmental Microbiology InteractionsUNSPECIFIED
Heritage Medical FoundationUNSPECIFIED
Record Number:CaltechTHESIS:08222018-105935103
Persistent URL:
Related URLs:
URLURL TypeDescription adapted for Ch. 5
Schretter, Catherine Elizabeth0000-0002-3957-6838
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:11154
Deposited By: Catherine Schretter
Deposited On:27 Aug 2018 21:18
Last Modified:04 Oct 2019 00:23

Thesis Files

PDF - Final Version
See Usage Policy.


Repository Staff Only: item control page