Recent evidence suggests that deep-sea vestimentiferan tube worms acquire their endosymbiotic bacteria from the environment each generation; thus, free-living symbionts should exist. Here, free-living tube worm symbiont phylotypes were detected in vent seawater and in biofilms at multiple deep-sea vent habitats by PCR amplification, DNA sequence analysis, and fluorescence in situ hybridization. These findings support environmental transmission as a means of symbiont acquisition for deep-sea tube worms.
Applied and Environmental Microbiology
Harmer, Tara L.; Rotjan, Randi D.; Nussbaumer, Andrea D.; Bright, Monika; Ng, Andrew W.; DeChaine, Eric G.; and Cavanaugh, Colleen M., "Free-Living Tube Worm Endosymbionts Found at Deep-Sea Vents" (2008). Biology. Paper 6.