Meeting Abstract

P2.154  Saturday, Jan. 5  Variation in anti-microbial activity in egg masses of 19 mollusc species in relation to variation in habitat an deposition site SMOOT, S.C.*; PLANTE, C.J.; PODOLSKY, R.D.; College of Charleston; College of Charleston; College of Charleston scsmoot@gmail.com

Gelatinous egg masses are used by several species of marine invertebrates to encapsulate embryos until hatching. The high protein and mucopolysaccharide composition of these egg masses make them particularly susceptible to microbial infection. Previous studies have found chemical compounds in benthic egg masses that deter microbial infection. Furthermore, levels of anti-microbial activity vary by field location and deposition site. We compared the antimicrobial activity of egg masses from 18 molluscan species that varied in deposition substrate and field site around the San Juan Islands, WA. Egg masses were collected from the field, lyophilized, and extracted with non-polar ethyl acetate (EtOAc) and polar methanol (MeOH) solvents. The extracts were then tested and quantified for antimicrobial activity against two marine pathogens: Bacillus subtilis and Vibrio harveyi, and three environmental pathogens in a 96-well plate assay. We observed differences in the anti-microbial activity among different molluscan species with the strongest inhibition in extracts of the cephalaspids Haminoea vesicula and Melanochlamys diomedea. Anti-microbial activity also appeared to vary among egg masses within species that had been deposited on different substrates. These results suggest wide interspecific and intraspecific variation in the degree of anti-microbial protection afforded by encapsulating structures. We are examining whether these patterns of protection suggest a greater role for the type of encapsulating structure or for the microenvironment at the site of deposition.