Wide bacterial diversity associated with tubes of the vent worm Riftia pachyptila.
We carried out a 16S rDNA-based molecular survey of the prokaryotic diversity associated with the chitin tubes of the giant vent tubeworm Riftia pachyptila (collected at the East Pacific Rise, 9 degrees N and 13 degrees N). Scanning electron microscopy showed dense microbial populations, particularly on the external surface of the middle and upper tube regions, which included very diverse prokaryotic morphotypes. We used archaeal- and bacterial-specific primers for polymerase chain reaction (PCR) amplification, but only bacterial amplicons were obtained. We analysed a total of 87 clones. Most belonged to the epsilon-Proteobacteria, but also to the delta-, alpha- and gamma-Proteobacteria. A broad diversity of phylotypes belonging to other bacterial divisions was detected, including Verrucomicrobia, the Cytophaga-Flavobacterium-Bacteroides group and the candidate division OP8. We also retrieved a sequence, R76-B150, of uncertain phylogenetic affiliation, which could represent a novel candidate division. The sequence of the R. pachyptilagamma-proteobacterial endosymbiont was not detected. The bacterial diversity found suggests that complex metabolic interactions, particularly based on sulphur chemistry, may be occurring in different microniches of the R. pachyptila tubes.
López-García
Purificación
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UMR 7622 CNRS, Laboratoire de Biologie Marine, Université Pierre et Marie Curie, 7, quai St Bernard, 75005 Paris, France. puir.lopez@snv.jussieu.fr
Gaill
Françoise
F
Moreira
David
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D000818:Animals; D004269:DNA, Bacterial / Q000032:analysis; D005057:Eukaryotic Cells / Q000382:microbiology*; D008386:Marine Biology; D008855:Microscopy, Electron, Scanning; D008969:Molecular Sequence Data; D010802:Phylogeny; D020560:Proteobacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D014871:Water Microbiology
D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S