Meeting Abstract
P1.88 Sunday, Jan. 4 Allelopathy in the symbiotic bacterium Vibrio fischeri; competitive exclusion prior to or during host infection? RIVERA, F. M.*; SOTO, W.; NISHIGUCHI, M. K.; New Mexico State Univeristy, Las Cruces; New Mexico State Univeristy, Las Cruces; New Mexico State Univeristy, Las Cruces fmrivera@nmsu.edu
Many interactions exist between large varieties of organisms, including bacteria that are found in free-living habitats. One type of interaction is allelopathy, which is the process of organisms excreting chemical substances to inhibit or kill closely related strains or species. Bacteria have the capacity to use allelopathic behavior for mechanisms such as infection, colonization, and competition. Specifically, symbiotic associations that harbor environmentally transmitted bacteria have the ability to promote this type of behavior between competing strains prior to or during colonization. In this study, we are testing whet specific strains of the squid symbiont Vibrio fischeri, experience antagonistic relationships as a result of exudate productions and/or milieu alterations that inhibit growth. We have used a series of cross inoculations between competing V. fischeri strains with spent media to determine whether certain strains are promoting any type of allelopathy. Results from previous research indicate that bacterial species do have an effect upon the growth of competing strains, and that specific substrates induce luminescence of V. fischeri, suggesting that intraspecific interactions occur prior or during the infection of squid light organs. Understanding the mechanisms of Vibrio allelopathy will provide insight as to why such genetic diversity exists among Vibrio symbionts, and whether their ecology is determined by both abiotic and biotic factors. Furthermore, this study may lead to the identification of certain chemical compounds produced by V. fischeri that contain properties to inhibit other Vibrio bacteria, including strains that are harmful to fisheries or pathogenic to organisms.
