Coordinates: Movile Cave (Romanian: Peștera Movile) is a cave near Mangalia, Constanța County, Romania discovered by Cristian Lascu in 1986 a few kilometers from the Black Sea coast. It is notable for its unique groundwater ecosystem rich in hydrogen sulfide and carbon dioxide but low in oxygen. Life in the cave has been separated from the outside for the past 5.5 million years and it is based completely on chemosynthesis rather than photosynthesis.
The air in the cave is very different from the outer atmosphere. The level of oxygen is only a third to half of the concentration found in open air (7–10% O2 in the cave atmosphere, compared to 21% O2 in air), and about one hundred times more carbon dioxide (2–3.5% CO2 in the cave atmosphere, versus 0.03% CO2 in air). It also contains 1–2% methane (CH4) and both the air and waters of the cave contain high concentrations of hydrogen sulfide (H2S) and ammonia (NH3).
Forty-eight species, among them leeches, spiders and a water scorpion are known from the cave, of which 33 are endemic. The food chain is based on chemosynthesis in the form of methane- and sulfur-oxidising bacteria, which in turn release nutrients for fungi and other bacteria. This forms microbial mats on the cave walls and the surface of lakes and ponds which are grazed on by some of the animals. The grazers are then preyed on by predatory species. Nepa anophthalma is the only known cave-adapted water scorpion in the world. While animals have lived in the cave for 5.5 million years, not all of them arrived simultaneously. The most recent animal recorded is the cave's only snail, which has inhabited the cave for slightly more than 2 million years.
In biochemistry, chemosynthesis is the biological conversion of one or more carbon-containing molecules (usually carbon dioxide or methane) and nutrients into organic matter using the oxidation of inorganic compounds (e.g., hydrogen gas, hydrogen sulfide) or methane as a source of energy, rather than sunlight, as in photosynthesis. Chemoautotrophs, organisms that obtain carbon through chemosynthesis, are phylogenetically diverse, but also groups that include conspicuous or biogeochemically-important taxa include the sulfur-oxidizing gamma and epsilon proteobacteria, the Aquificae, the methanogenic archaea and the neutrophilic iron-oxidizing bacteria.
Many microorganisms in dark regions of the oceans use chemosynthesis to produce biomass from single carbon molecules. Two categories can be distinguished. In the rare sites at which hydrogen molecules (H2) are available, the energy available from the reaction between CO2 and H2 (leading to production of methane, CH4) can be large enough to drive the production of biomass. Alternatively, in most oceanic environments, energy for chemosynthesis derives from reactions in which substances such as hydrogen sulfide or ammonia are oxidized. This may occur with or without the presence of oxygen.
Many chemosynthetic microorganisms are consumed by other organisms in the ocean, and symbiotic associations between chemosynthesizers and respiring heterotrophs are quite common. Large populations of animals can be supported by chemosynthetic secondary production at hydrothermal vents, methane clathrates, cold seeps, whale falls, and isolated cave water.
It has been hypothesized that chemosynthesis may support life below the surface of Mars, Jupiter's moon Europa, and other planets. Chemosynthesis may have also been the first type of metabolism that evolved on Earth, leading the way for cellular respiration and photosynthesis to develop later.Deep sea community
A deep sea community is any community of organisms associated by a shared habitat in the deep sea. Deep sea communities remain largely unexplored, due to the technological and logistical challenges and expense involved in visiting this remote biome. Because of the unique challenges (particularly the high barometric pressure, extremes of temperature and absence of light), it was long believed that little life existed in this hostile environment. Since the 19th century however, research has demonstrated that significant biodiversity exists in the deep sea.
The three main sources of energy and nutrients for deep sea communities are marine snow, whale falls, and chemosynthesis at hydrothermal vents and cold seeps.Gamma-Glutamylmethylamide
γ-Glutamylmethylamide (gamma-Glutamylmethylamide, abbrev. GMA, synonyms N-methyl-L-glutamine, metheanine) is an amino acid analog of the proteinogenic amino acids L-glutamic acid and L-glutamine, found primarily in plant and fungal species; simply speaking, it is L-glutamine methylated on the amide nitrogen. It is an identified an important biosynthetic intermediate allowing bacteria (e.g., methanotrophs) use of methylated amines as carbon and nitrogen source for growth (and so of significant biotechnological interest). Like its close relative theanine, it is a pharmacologically active constituent of green tea, with preliminary evidence for at least comparable activity to theanine as a hypotensive.Hydrogen sulfide
Hydrogen sulfide is the chemical compound with the formula H2S. It is a colorless chalcogen hydride gas with the characteristic foul odor of rotten eggs. It is very poisonous, corrosive, and flammable.Hydrogen sulfide is often produced from the microbial breakdown of organic matter in the absence of oxygen gas, such as in swamps and sewers; this process is commonly known as anaerobic digestion which is done by sulfate-reducing microorganisms. H2S also occurs in volcanic gases, natural gas, and in some sources of well water. The human body produces small amounts of H2S and uses it as a signaling molecule.Swedish chemist Carl Wilhelm Scheele is credited with having discovered the chemical composition of hydrogen sulfide in 1777.
The British English spelling of this compound is hydrogen sulphide, but this spelling is not recommended by the International Union of Pure and Applied Chemistry (IUPAC) or the Royal Society of Chemistry.List of caves
This is a list of caves of the world, sorted by continent and then country.Mars habitability analogue environments on Earth
Mars habitability analogue environments on Earth are environments that share potentially relevant astrobiological conditions with Mars. These include sites that are analogues of potential subsurface habitats, and deep subsurface habitats.A few places on Earth, such as the hyper-arid core of the high Atacama Desert and the McMurdo Dry Valleys in Antarctica approach the dryness of current Mars surface conditions. In some parts of Antarctica, the only water available is in films of brine on salt / ice interfaces. There is life there, but it is rare, in low numbers, and often hidden below the surface of rocks (endoliths), making the life hard to detect. Indeed, these sites are used for testing sensitivity of future life detection instruments for Mars, furthering the study of astrobiology. For instance, as a location to test microbes for their ability to survive on Mars, and as a way to study how Earth life copes in conditions that resemble conditions on Mars.
Other analogues duplicate some of the conditions that may occur in particular locations on Mars. These include ice caves, the icy fumaroles of Mount Erebus, hot springs, or the sulfur rich mineral deposits of the Rio Tinto region in Spain. Other analogues include regions of deep permafrost and high alpine regions with plants and microbes adapted to aridity, cold and UV radiation with similarities to Mars conditions.Movile
Movile may refer to:
Movile, a village in the commune Iacobeni, Sibiu County, Romania
Movile Cave in Constanța County, Romania