Phylogenetic characterization of the bacterial assemblage associated with mucous secretions of the hydrothermal vent polychaete Paralvinella palmiformis

Abstract

As part of an ongoing examination of microbial diversity associated with hydrothermal vent polychaetes of the family Alvinellidae, we undertook a culture-independent molecular analysis of the bacterial assemblage associated with mucous secretions of the Northeastern Pacific vent polychaete Paralvinella palmiformis. Using a molecular 16S rDNA-based phylogenetic approach, clone libraries were constructed from two samples collected from active sulfide edifices in two hydrothermal vent fields. In both cases, clone libraries were largely dominated by epsilon-Proteobacteria. Phylotypes belonging to the Cytophaga-Flavobacteria and to the Verrucomicrobia were also largely represented within the libraries. The remaining sequences were related to the taxonomic groups Fusobacteria, Green non-sulfur bacteria, Firmicutes, gamma- and delta-Proteobacteria. To our knowledge, this is the first report of the presence of Verrucomicrobia, Fusobacteria and green non-sulfur bacteria on hydrothermal edifices. The potential functions of the detected bacteria are discussed in terms of productivity, recycling of organic matter and detoxification within the P. palmiformis microhabitat.

Geomicrobial characterization of gas hydrate-bearing sediments along the mid-Chilean margin

“…One group of Verrucomicrobia clones were 100% similar to clones from Svalbard sediments (Table 4). The remaining Verrucomicrobia clones were ≥92% similar to other clones from marine sediments (Alain et al ., 2002; Inagaki et al ., 2006). The Verrucomicrobia are widely distributed in the environment (Hedlund et al ., 1996), and numerous reports have identified Verrucomicrobia relatives in marine sediments (Alain et al ., 2002; Teske et al ., 2002; Mills et al ., 2004; Inagaki et al ., 2006).…”

Psychrilyobacter atlanticus gen. nov., sp. nov., a marine member of the phylum Fusobacteria that produces H2 and degrades nitramine explosives under low temperature conditions

“…AJ877255) and strain Ko711 from Kolbeinsey Ridge, Iceland (99.5 % similarity, GenBank accession no. AF550592), and to six deep-sea environmental sequences (Alain et al, 2002(Alain et al, , 2004Goffredi et al, 2005) obtained from clone libraries (Fig. 1).…”

Gramella echinicola gen. nov., sp. nov., a novel halophilic bacterium of the family Flavobacteriaceae isolated from the sea urchin Strongylocentrotus intermedius

“…Also, the representatives of this group are considered to be an important part of marine-animal microbial populations, as indicated by data from culture-independent molecular analyses (Cooney et al, 2002;Ló pez-García et al, 2002;Webster et al, 2004). For example, Alain et al (2002) examined the microbial assemblage associated with the hydrothermal vent polychaete Paralvinella palmiformis of the north-eastern Pacific by using 16S rRNA gene sequencebased phylogenetic analysis; they reported that members of the Cytophaga-Flavobacterium group were identified frequently in 16S rRNA gene clone libraries.…”