Marine bacteria produce compounds that modulate multixenobiotic transport activity in Urechis caupo embryos

Marine bacteria isolated from the intestine of the sediment-dwelling worm, Urechis caupo, produce compounds that are potential substrates of the multixenobiotic transport protein in Urechis embryos. Three strains isolated from the intestines of two worms were identified as Vibrio harveyi, Vibrio vulnificus and Shewanella putrefaciens. A fourth strain was not identified. Compounds extracted from V. harveyi were most effective at modulating dye transport in Urechis embryos. However, an extract of V. harveyi obtained from American Type Culture Collection (ATCC) did not affect dye accumulation in the embryos suggesting differences in the two isolates. This may be due to a difference in plasmids isolated from both strains (two plasmids were found in the Urechis isolate while no plasmids were found in the ATCC strain). Thus, the multixenobiotic defense mechanism may be important in Urechis adults and embryos to protect this organism from compounds produced by bacteria in the sediment to which the worm may be exposed or may ingest.