Hydrothermal vent animals

Rubisco of Bacterial Endosymbionts of Hydrothermal Vent Animals Undersea hydrothermal vents support remarkable ecosystems. At these extreme depths there is no light to support photosynthesis, yet thriving vent communities are found. Much of their primary productivity occurs through chemosynthesis carried out by bacterial symbionts that live in specialized organs (trophosomes) of... 

Grassle JF (1985) Hydrothermal vent animals distribution and biology. Science 229 713-717 Gray KA, Grooms M, Myllykalho H, Moomaw C, Slaughter C, Daldal F (1994) Rhodobacter capsulatus contains a novel cb-type cytochrome c oxidase without a Cua center. Biochemistry 33 3120-3127... 

Only deep-sea hydrothermal vents and cold-seeps are discussed in this chapter. Shallow vents and seeps are known from a variety of locations, from the littoral zone to several tens of metres (e.g. Holm, 1987 Jensen etal., 1992 Dando etal., 1994a,b, 1995). Shallow vents have many differences from their deeper counterparts. They lack metal-rich and extreme high temperature fluids, as well as large-scale mineral deposits. They also lack typical hydrothermal vent animals. Biomass production in both systems is lower than at deep-sea vents and deep... 

Childress, J.J. and Fisher, C.R. (1992) The biology of hydrothermal vent animals physiology, biochemistry, and autotrophic symbioses. Oceanogr. Mar. Biol. Annu. Rev., 30, 337—441. 

Many vent microbes are symbionts. Others form dense filamentous mats, such as the sulfide oxidizers Beggiatoa (oxic) and Thioploca (hypoxic). Similar mats probably develop subsurface within hydrothermal conduits. These subsurface mats are ejected into the water column during first stage of vent formation. The resulting explosive discharge of this biomass, which has the appearance of a white floe, has given rise to the term snowblower vent. The ejected microbes are thought to eventually settle back down onto the seafloor where they increase in number to form surficial mats that support the successional colonization of vent animals. 

If we consider the animals as gutless tubeworms that live at highly sul-fidic hydrothermal vents (discussed, for example, in Vetter et al. 1991), then we see that there are many forms that depend upon sulfide and we are faced with the question did they invent this basic biochemistry to handle sulfide de novo or is it a holdover from earlier times ... 

Around deep-sea vents lives a very interesting species of animal the tubeworm. Some tubeworms can grow to be almost 8 feet (3 m) long. They were first discovered in the 1970s around some hydrothermal vents near the Galapagos Islands off the coast of South America. Since then many tubeworms have been found at deep-sea vents all over the world. 

The study of sulfide metabolism at hydrothermal vents dictated the development of methods that could process hundreds of samples which contain complex mixtures of sulfur compounds in a variety of blood, seawater and tissues samples. In addition, we needed the capability of using "S-radiolabeled compounds for the tracing of complex sulfur metabolic pathways in bacteria and animal compartments of the different hydrothermal vent symbioses. In some instances, in situ sampling by submersibles at depths of 2500 meters with associated recovery times of two hours necessitated the remote derivatization of samples at depth prior to recovery. None of the above methods completely met our needs. We have adapted the bimane-HPLC method (24.351 for shipboard use and have found it a particularly robust method for studying a number of questions concerning the role of reduced sulfur compounds in the marine environment. 

Among differently adapted species of fishes and invertebrates, the ABT of mitochondrial respiration varies regularly with adaptation temperature (figure 7.23, lower panel). The animals that were compared included deep-sea invertebrates from both warm (hydrothermal vent) and cold habitats plus several shallow occurring marine invertebrates and fishes adapted to widely different temperatures, including the Antarctic fish Trematomus ber-nacchii (boxed + symbol Dahlhoff et al., 1991 Weinstein and Somero, 1998). Also... 

Fig. 4.6. A schematic presentation showing that the bacterium (or bacteria) of Beggiatoa genus and various animals reside around the hydrothermal vents...

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