Riftia pachyptila - Wikipedia
The HHMI film How Giant Tube Worms Survive at Hydrothermal Vents is one of 12 have a symbiotic relationship with species of chemosynthetic bacteria. Riftia pachyptila, commonly known as giant tube worms, are marine invertebrates in the phylum Tube worms have no digestive tract, but the bacteria (which may make up half of a . "Biochemical and enzymological aspects of the symbiosis between the deep-sea tubeworm Riftia pachyptila and its bacterial endosymbiont ". The giant tube worm, also known to science as Riftia pachyptila, were totally unknown to Instead, they feed on tiny bacteria that get their energy directly from the beneficial relationship between two organisms is known as symbiosis.
The proteome revealed telltale enzymes, which the bacteria use to harness chemical energy and to fix inorganic carbon.
The combined genomic and proteomic approaches offer a valuable way to investigate the metabolic capabilities and history of these microorganisms, said Charles Fisher of Pennsylvania State University and Peter Girguis of Harvard University, who wrote a perspective article on the research in Science. The new study solves one mystery that had been puzzling scientists for decades. They had found that tubeworm tissues contain more of a heavier stable carbon isotope than expected if the Calvin cycle were the only one at work.
Use of the rTCA cycle explains this conundrum, because it results in the incorporation of more of the heavy stable carbon isotope, compared to the Calvin cycle, Sievert said.
Giant tube worm videos, photos and facts - Riftia pachyptila | Arkive
The Calvin cycle works with plenty of oxygen around, Sievert explained, but requires substantially more energy than the rTCA cycle, which, on the other hand, is inhibited by higher oxygen concentrations. Such metabolic flexibility is an asset in habitats dependent on the fluctuating flows of fluids emanating from hydrothermal vents, he said.
A relationship with give and take For a long time, the means by which the tubeworms Riftia pachyptila acquired the symbionts had remained a mystery as well, with many investigators thinking that the worms may pick up the bacteria in their larval stage, when the worms still have a mouth.
This feat is accomplished by a special type of hemoglobin in their blood that can transport oxygen and sulfide at the same time human hemoglobin transports only oxygen.
Riftia pachyptila Symbiosis with Thioautotrophic Bacteria
The bacteria inside the tubeworms oxidize hydrogen sulfide to create energy. In this case, the worm gives the bacteria a place to stay and the bacteria provide food for the worm. This worm, called Riftia pachyptila, is an unusual animal because it has no mouth or digestive tract and no apparent way to eat!Weird Worms Live Near Pacific Ocean’s Deepest High-Temp Vent - National Geographic
Instead of eating food like other animals, Riftia allows bacteria to live inside of it and provide its food. The worms have a special feeding sac, called a trophosomewhich provides the bacteria with shelter and ingredients to make food.
In turn, the bacteria use these ingredients to make food for the worm.
Giant Tube Worm
The trophosome and the bacteria inside it are so important that they make up over half the weight of this animal. Strange Life in the Dark Dark ocean floors near deep sea vents are home to giant clams, shrimps, tube worms, crabs and other strange creatures.
When these communities were first discovered living deep on the dark ocean floor, no one know how life could exist there without sunlight. Until recently, people thought that all food ultimately comes from plants and other photosynthetic creatures like algae and cyanobacteria. These photosynthesizers use energy from sunlight to convert carbon dioxide into food. Organisms that make food for an entire community are called primary producers. But who are the primary producers deep under water where there is no light?
These bacteria, like the ones in the picture above, get their energy from chemicals flowing out of the volcanic vents, not from energy found in sunlight.
Hydrogen sulfide, the stuff that smells like rotting eggs and is toxic to us, is one of the main chemicals used by the vent bacteria for making food.
These bacteria make energy by combining hydrogen sulfide with oxygen also supplied by the tube worms to make sulfur, water and energy. The bacteria then uses this energy to convert carbon dioxide into food just like plants use energy from the sun to make food.
This food in turn feeds the entire community of worms, clams, crabs and other creatures.
Microbe of the Month
In the case of the tube worm, the bacteria living inside the worm use the hydrogen sulfide supplied by the worm. The worm collects the hydrogen sulfide with its red feathery cap.
This cap is red because it is filled with blood containing a special hemoglobin that transports the hydrogen sulfide to the bacteria. The tubeworm also provides the symbionts with oxygen which it needs to combine with the hydrogen sulfide for energy.