In Situ Determination of Bacterial Growth in Mixing Zone of Hydrothermal Vent Field on the Hatoma Knoll, Southern Okinawa Trough

摘要: The doubling time of indigenous bacteria in mixing-zone hydrothermal fluid and seawater was determined using a diffusion chamber unit deployed on the field Hatoma Knoll (24° 51.50′N, 123° 50.50′ E), which is submarine volcano located southern Okinawa Trough. reliable tool to incubate directly measure microbial growth under situ condition deep-sea, although an operation submersible complicated preparation seed water became technical constraints. at non-vent site distant from active vent estimated 86 110 h, while sites more rapid time, 21–32 were estimated. A potential sulfur-oxidizing belonging Epsilonproteobacteria dominated population grew chambers, incubated plume obtained mixing zone between seawater, Bathymodiolus colony, no detection Gammaproteobacteria. methane-oxidizing detected only gill digestive tract platifrons, could not be chamber, placed colony. results this study suggested that chemolithoautotrophic near by sustained chemical species dissolved provides chemoautotrophic product deep-sea benthopelagic community, as well products plume.