ena-STUDY-Virginia Commonwealth University-25-06-2014-16:22:05:615-583
A metagenomic assessment of the bacteria associated with Lucilia sericata and Lucilia cuprina (Diptera: Calliphoridae)
Lucilia Robineau-Desvoidy (Diptera: Calliphoridae) is a blow fly genus of forensic, medical, veterinary, and agricultural importance. Species of this genus can cause myiasis, and are mechanical vectors of disease-causing bacteria. This genus is also famous because of its beneficial uses in maggot debridement therapy (MDT). Although the genus is of considerable economic importance, our knowledge about microbes associated with these flies, and how these bacteria are horizontally and trans-generationally transmitted is limited. In this study, we characterized bacteria associated with different life stages of Lucilia cuprina and L. sericata and in salivary gland of L. sericata by using 16S rDNA 454-pyrosequencing. Bacteria associated with salivary gland of L. sericata were also characterized using light and transmission electron microscopy (TEM). Results from this study suggest that the majority of bacteria associated with these flies belong to phyla Proteobacteria, Firmicutes, and Bacteroidetes, and most bacteria are maintained intra-generationally, with a considerable degree of turnover from generation to generation. In unweighted FastUniFrac clustering bacterial structure of first generation eggs (G1egg) was more similar to bacterial structure of adult female flies than to adult male flies, and (Adult male + (G1egg + Adult female)) was sister group of (larval + pupal) samples. Second-generation eggs (G2egg) shared the least number of bacteria with other life stages. Bacteria belonging to phyla Acidobacteria and Actinobacteria were mainly present in G2egg samples in both species. Although Lucilia sister species shared the majority of their classified genera, there were some that were unique to each species, but they were present at relatively low abundances. Of the shared bacterial genera Providencia, Ignatzschineria, Lactobacillus, Lactococcus, Vagococcus, Morganella, and Myroides were present at relatively high abundances. Lactobacillus, Proteus, Diaphorobacter, and Morganella were dominant bacterial genera associated with the salivary gland of L. sericata. TEM analysis showed sparse distribution of both Gram positive and Gram negative bacteria in the salivary gland of L. sericata. There was more evidence for horizontal transmission of bacteria than there was for trans-generational inheritance. Several pathogenic genera were either amplified or reduced by the larval feeding on decomposition of liver as a resource. Overall, this study provides information on bacterial communities associated with different life stages of the Lucilia, and their horizontal and trans-generational transmission, which may help in development of better vector-borne disease management and MDT methods.
Lucilia Robineau-Desvoidy (Diptera: Calliphoridae) is a blow fly genus of forensic, medical, veterinary, and agricultural importance. Species of this genus can cause myiasis, and are mechanical vectors of disease-causing bacteria. This genus is also famous because of its beneficial uses in maggot debridement therapy (MDT). Although the genus is of considerable economic importance, our knowledge about microbes associated with these flies, and how these bacteria are horizontally and trans-generationally transmitted is limited. In this study, we characterized bacteria associated with different life stages of Lucilia cuprina and L. sericata and in salivary gland of L. sericata by using 16S rDNA 454-pyrosequencing. Bacteria associated with salivary gland of L. sericata were also characterized using light and transmission electron microscopy (TEM). Results from this study suggest that the majority of bacteria associated with these flies belong to phyla Proteobacteria, Firmicutes, and Bacteroidetes, and most bacteria are maintained intra-generationally, with a considerable degree of turnover from generation to generation. In unweighted FastUniFrac clustering bacterial structure of first generation eggs (G1egg) was more similar to bacterial structure of adult female flies than to adult male flies, and (Adult male + (G1egg + Adult female)) was sister group of (larval + pupal) samples. Second-generation eggs (G2egg) shared the least number of bacteria with other life stages. Bacteria belonging to phyla Acidobacteria and Actinobacteria were mainly present in G2egg samples in both species. Although Lucilia sister species shared the majority of their classified genera, there were some that were unique to each species, but they were present at relatively low abundances. Of the shared bacterial genera Providencia, Ignatzschineria, Lactobacillus, Lactococcus, Vagococcus, Morganella, and Myroides were present at relatively high abundances. Lactobacillus, Proteus, Diaphorobacter, and Morganella were dominant bacterial genera associated with the salivary gland of L. sericata. TEM analysis showed sparse distribution of both Gram positive and Gram negative bacteria in the salivary gland of L. sericata. There was more evidence for horizontal transmission of bacteria than there was for trans-generational inheritance. Several pathogenic genera were either amplified or reduced by the larval feeding on decomposition of liver as a resource. Overall, this study provides information on bacterial communities associated with different life stages of the Lucilia, and their horizontal and trans-generational transmission, which may help in development of better vector-borne disease management and MDT methods.