Honors Theses and Capstones

Date of Award

Fall 2012

Project Type

Senior Honors Thesis

College or School



Biological Sciences

Program or Major

Medical and Veterinary Sciencess

Degree Name

Bachelor of Science

First Advisor

Cheryl Whistler


Vibrio fischeri and Euprymna scolopes squid establish mutualistic symbiosis and select for each other in the natural environment. V. fischeri provides bioluminescent camouflage for E. scolopes while E. scolopes provides nutrients for V. fischeri. The most intriguing aspect of this relationship is that E. scolopes is highly selective and only allows sustained colonization by luminous, but not dark V. fischeri. Luminescence is the key symbiosis trait; however, other bacterial factors may also allow squid recognition. We hypothesized that there are luminescence linked traits that contribute to colonization. V. fischeri with luminescence variation was isolated and tested for oxidative resistance, morphology, siderophore, biofilm, chitinase activity, motility, and auxotrophy. Siderophore and chitinase activity demonstrated correlation with luminescence while all other phenotypes didn’t demonstrate direct relations.