Evidence for selective bacterial community structuring in the freshwater sponge Ephydatia fluviatilis. | - CCMAR -

Journal Article

TitleEvidence for selective bacterial community structuring in the freshwater sponge Ephydatia fluviatilis.
Publication TypeJournal Article
AuthorsCosta, R, Keller-Costa, T, Gomes, NCM, da Rocha, UNunes, van Overbeek, L, van Elsas, JDirk
Year of Publication2013
JournalMicrob Ecol
Date Published2013 Jan
KeywordsAnimals, Bacteria, Biodiversity, DNA, Bacterial, Fresh Water, Metagenome, Netherlands, Phylogeny, Porifera, RNA, Ribosomal, 16S, Sequence Analysis, DNA

To understand the functioning of sponges, knowledge of the structure of their associated microbial communities is necessary. However, our perception of sponge-associated microbiomes remains mainly restricted to marine ecosystems. Here, we report on the molecular diversity and composition of bacteria in the freshwater sponge Ephydatia fluviatilis inhabiting the artificial lake Vinkeveense Plassen, Utrecht, The Netherlands. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) fingerprints revealed that the apparent diversities within the domain Bacteria and the phylum Actinobacteria were lower in E. fluviatilis than in bulk water. Enrichment of specific PCR-DGGE bands in E. fluviatilis was detected. Furthermore, sponge- and bulk water-derived bacterial clone libraries differed with respect to bacterial community composition at the phylum level. E. fluviatilis-derived sequences were affiliated with six recognized phyla, i.e., Proteobacteria, Planctomycetes, Actinobacteria, Bacteroidetes, Chlamydiae and Verrucomicrobia, in order of relative abundance; next to the uncultured candidate phylum TM7 and one deeply rooted bacterial lineage of undefined taxonomy (BLUT). Actinobacteria, Proteobacteria, and Bacteroidetes were the dominant bacterial phyla in the freshwater clone library whereas sequences affiliated with Planctomycetes, Verrucomicrobia, Acidobacteria and Armatimonadetes were found at lower frequencies. Fine-tuned phylogenetic inference showed no or negligible overlaps between the E. fluviatilis and water-derived phylotypes within bacterial taxa such as Alphaproteobacteria, Bacteroidetes and Actinobacteria. We also ascertained the status of two alphaproteobacterial lineages as freshwater sponge-specific phylogenetic clusters, and report on high distinctiveness of other E. fluviatilis specific phylotypes, especially within the Bacteroidetes, Planctomycetes and Chlamydia taxa. This study supports the contention that the composition and diversity of bacteria in E. fluviatilis is partially driven by the host organism.



Alternate JournalMicrob. Ecol.
PubMed ID22903086
CCMAR Authors