English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

Shipboard studies showed major differences in the incorporation of CO2 by the specific prokaryotic symbionts of two deep-sea vent invertebrates. The rate of CO2 fixation was optimal at approximately 22Â°Cin fresh trophosome material from the pogonophoran tube worm R@/1iapachyptila. Sulfide, but not thiosulfate, served as the electron donor. Thirty-five percent ofthe aerobic rate remained in deoxygenated sam pies presumablydue to traces of hemoglobin-bound oxygen. Gill preparationsfrom the mytilid mussel Bathymodiolus thermophilus,however, assimilated CO2 with a maximum rate at 12Â° to 15Â°C. Thiosulfate, but not sulfide, served as the electron donor.The activitywascompletelyinhibitedin deoxygenatedsamples.Thesemetabolic dissimilarities between the symbionts ofthe two hosts extend to DNA base ratios and cell sizes. Partialfractionationofthe mussel gill preparationyielded a prokaryoticor â€œ?bacterialâ€ fraction that showed a CO2 assimilation rate three-fold higher than that of the crude homogenate. This activity was not affected by the in situ hydrostatic pressure of 250 atm (100% barotolerance). The mussel gill symbiont represents the first sulfur-oxidizing vent prokaryote with psychrophilic growth characteristics. The natural distribution ofR. pachyptila and B. thermophilus within the physico-chemical regime ofthe immediate vent vicinity corresponds well with the metabolic differences oftheir symbionts.

biological bulletin

SYMBIOTIC ASSIMILATION OF CO2IN TWO HYDROTHERMAL VENT ANIMALS, THE MUSSELBATHYMODIOLUS THERMOPHILUSAND THE TUBE WORMRIFTIA PACHYPTILA