To begin Alissa's talk you can click here or read this brief overview, below, that provides links to the best places in the talk for specific topics.
Alissa J. Arp, Ph.D., Director and Professor, Romberg
Tiburon Center for Environmental Studies, San
Francisco State University presents aspects of physiology in marine invertebrates
exposed to energy rich, but highly toxic, hydrogen sulfide in three different environments. Various sulfide detoxification strategies are employed
by marine animals in these sulfide environments. Some organisms contain symbiotic, chemosynthetic bacteria. These symbionts detoxify the sulfide and provide nutrition for their hosts. Others do not contain symbionts, and detoxify sulfide through physiological pathways.
In the deep-sea hydrothermal vents, chemoautotrophic
endosymbiont-harboring worms, Riftia pachyptila , clams
and mussels utilize sulfide to fuel bacterial metabolism while
protecting their tissues from toxicity by the sulfide detoxification
process of binding the sulfide to blood-borne components.
In cold seeps, chemosynthetic communities congregate
around naturally seeping pools of sulfide, methane and hypersaline
brine. Chemosynthetic mussels utilize methane as their inorganic
energy supply. Newly discovered polychaete worms colonize mounds
of frozen methane.
In estuarine mudflats at low tides, the non-chemosynthetic,
echiuran worm, Urechis caupo, is exposed to toxic sulfide.
The animal tolerates moderate sulfide levels through physiological adaptations that protect the body tissues and internal