Symbiont-driven sulfur crystal formation in a thiotrophic symbiosis from deep-sea hydrocarbon seeps.
Bottom Line: This suggests that their formation is either extra- or intracellular in symbionts.We propose that formation of these crystals provides both energy-storage compounds for the symbionts and serves the symbiosis by removing excess toxic sulfide from host tissues.This symbiont-mediated sulfide detoxification may have been crucial for the establishment of thiotrophic symbiosis and continues to remain an important function of the symbionts.
Affiliation: Department of Limnology and Oceanography, Faculty of Life Sciences, University of Vienna, Althanstr. 14, 1090, Vienna, Austria.Show MeSH
Related in: MedlinePlus
Mentions: Five specimens fixed in 4% formaldehyde buffered with 0.1 mol l–1 phosphate-buffered saline (PBS), 5.4 to 8.6 cm in length, revealed abundant, giant crystals that were even visible through the worm's tube under the dissecting microscope (Fig. 3A). Two kinds of water insoluble crystals were detected: tightly packed needle-shaped crystals up to 50 μm in length interspersed with clumps of orthorhombic crystals up to 150 μm in length (Fig. 3B–D). LM of whole mounts indicated a restricted distribution of the crystals to the posterior trophosomal tissue, which is deeply buried in sulfidic mud in situ. Further examination of semithin sections of high-pressure frozen and freeze-substituted samples, infiltrated by Lowicryl HM20 resin (Supporting information) under the LM indicated the crystals were located in cavities between bacteriocytes filled with symbionts (Fig. 3E).
Affiliation: Department of Limnology and Oceanography, Faculty of Life Sciences, University of Vienna, Althanstr. 14, 1090, Vienna, Austria.