MBIO 3280 Lecture Notes - Lecture 30: Trophosome, Tube Worm, Giant Tube Worm

• School: University of Manitoba
• Department: Microbiology
• Course: MBIO 3280
• Professor: Vladimir Yurkov

Document Summary

Tube worms riftia (very distant relative of earthworm) Structure: 1-2 m long, 10-15 cm diameter. High densities surrounding vents, high growth rates (if disturbed can be recovered very quickly) Plume is bright red from unusual hemoglobin. No mouth, anus, or intestinal tract: lamella used to absorb nutrients, heart like structure to pump blood, protection tube. Spongy tissue called trophosome dominates (half of weight of body) Many sulfur (s prime) granules in trophosome. Endosymbiotic association with chemolithoautotrophic bacteria: similar to marine sulfur-oxidizers, sulfide oxidizing bacteria ~ 109 cells/g tissue. Bacteria oxidize sulfide with oxygen as electron acceptor. Bacteria fix carbon dioxide (calvin cycle) into organic carbon that is either excreted, or released from decomposing bacteria this organic carbon is food for the tube worm (or clam, mussel) Tube worm (or mussel, clam) provides habitat and delivers substrates (o2, s-2, co2) to bacteria.