General Information: This strain was collected off Hatsushima island in Sagami Bay, Japan. Calyptogena okutanii (deep-sea clam) thioautotrophic gill symbiont. The bivalve marine species Calyptogena okutanii depends on sulfur-oxidizing symbiotic bacteria housed in its gill tissues for its sole nutritional support. The symbiont is transmitted vertically between generations via the clam's eggs. This anaerobic symbiosis oxidizes hydrogen sulfide as an energy source and fixes carbon dioxide into organic compounds.