In bioremediation, surfactants are used to emulsify hydrocarbon pollutants in water to make the hydrocarbons more accessible for breakdown by bacteria. Identification of bacterial species that have surfactant resistance is essential for the advancement of bioremediation techniques. One bacterial species, BGP-2 was isolated from Nereis succinea with the intention of being utilized for bioremediation due to its high surfactant resistance. Prior characterization of BGP-2 has shown that BGP-2 is a new species. To complete the classification of BGP-2, its GC content must be determined. Common methods for analyzing GC content include mass spectrometry and HPLC; both of which require training and access to equipment that are not readily present in biological laboratories. With increasing access to quantitative real time PCR thermocyclers, applications such as determining GC content have been devised. To assist in the classification of BGP-2, a standard curve of bacteria with well-known GC contents was generated using a Step One real time PCR thermocycler. We expect that experimental data from BGP-2 can be applied to the standard curve in order to determine its GC content. With knowledge of BGP-2’s GC content, it will be possible to place BGP-2 into a taxonomic rank.
Dept of Biological Sciences, Campbell University, Buies Creek, NC
Much literature exists regarding trematode-snail relationships, and several of those studies indicate that habitat is highly correlated with heterogeneous patterns in the prevalence of infection. While hypothesized in other work on parasite aggregation, dilution effects (where habitat size dictates the density of infective stage larvae per unit area) is rarely experimentally tested. This study directly investigates the relationship between habitat area and parasite aggregation in a model trematode-snail system. Previous work has demonstrated habitat-specific infection patterns in two trematode species (Himasthla quissetensis and Zoogonus rubellus) infecting the Eastern mudsnail (Ilyanassa obsoleta). In this study, we selected eight intertidal pannes (ranging in sizes from 5-50 m2) and surveyed the standing infections by sampling 100 snails from each panne in July, 2013. In each panne, we then installed three caged enclosures containing 50 uninfected snails each, and left them to accumulate new infections until late September. We predicted that smaller pannes would produce higher prevalence values than larger ones. Both sets of snail collections were then measured for size and parasite load. A partially completed dataset suggests that snails in small pannes are more prone to higher parasite loads (reaching 84% prevalence values), supporting the idea that these two trematodes can saturate small areas with infective stage larvae.
Diel Patterns of Parasite Larvae Production and Host Mortality in a Snail-Trematode System
Numerous studies have quantitatively reported on the production of parasite larvae with respect to individual hosts. The literature addressing trematode-snail patterns is particularly robust. Still, little attention has been given to the remarkable variation in larval (cercariae) production among individual hosts, or in the same host through time. In this study, we assessed patterns in the number of cercariae released by infected individuals on a day-to-day basis for trematodes infecting the mudsnail Ilyanassa obsoleta. We found that the variation in diel release of cercariae (SD = 189.97) was larger than the magnitude of mean cercarial production (184.67), and production ranged from 0-1476 in a single day. Patterns of larval release were not correlated among snails. As an extension of previous work on this system, we also experimentally evaluated the survivorship of infected individuals verses the uninfected individuals under stresses consistent with real environmental extremes. We found infected snails were more likely to die in situations of elevated temperature and salinity than those that were uninfected. This suggests that the infection has a negative effect on the survivorship of the snail, and might explain previously reported distribution of the parasite in host populations.
Dept of Biology, Waynesburg University, Waynesburg, PA
P178 • Brandon Denney, Riccardo Fiorillo
Seasonal Dynamics of Trematode Parasites of Three Elimia Species (Gastropoda: Pleuroceridae)in the Etowah River Basin in Northwest Georgia
We examined the seasonal dynamics of the trematode parasites of Elimiamodesta, E. carinifera, and E. carinicostata in the Etowah River basin located in Northwest Georgia. Approximately 400 snails were collected monthly from September 2013 through March 2014 from each of four locations in three small tributaries of the Etowah River (Euharlee, Two Run, and Connesena creeks). In the laboratory, snails were isolated in wells with approximately 60 ml of spring water and examined for actively shedding trematode cercariae two or more times over a three week period. Overall, we identified 13 cercariae morphotypes. Snails in Connesena Creek showed the highest trematode species richness and were infected with all morphotypes, while snails in Euharlee Creek, were only actively shedding 7 morphotypes. Cotylomicrocercous cercaria, shed by trematodes in the family Opecoelidae, was the most prevalent larval trematode and found in three of four sites. Prevalence of this trematode was lowest in our late summer collection and increased through fall and winter months. We also report on the seasonal prevalence of all remaining morphotypes and their patterns of occurrence across all sites. In addition, we also examined the seasonal prevalence of a commensal annelid, likely Chaetogaster limnaei limnaei and noted a positive correlation between annelid and trematode prevalence across collection sites.
School of Science and technology, Georgia Gwinnett College
