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Lithotroph
Lithotrophs are a diverse group of organisms using an inorganic substrate (usually of mineral origin) to obtain reducing equivalents for use in biosynthesis (e.g., carbon fixation, carbon dioxide fixation) or energy conservation (i.e., Adenosine triphosphate, ATP production) via Cellular respiration, aerobic or anaerobic respiration. While Primary nutritional groups#Primary sources of reducing equivalents, lithotrophs in the broader sense include photolithotrophs like plants, Chemotroph, chemolithotrophs are exclusively microorganisms; no known fauna#Macrofauna, macrofauna possesses the ability to use inorganic compounds as electron sources. Macrofauna and lithotrophs can form symbiotic relationships, in which case the lithotrophs are called "prokaryotic symbionts". An example of this is chemolithotrophic bacteria in giant tube worms or plastids, which are organelles within plant cells that may have evolved from photolithotrophic cyanobacteria-like organisms. Chemolithotrophs belon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primary Nutritional Groups
Primary nutritional groups are groups of organisms, divided in relation to the nutrition mode according to the sources of energy and carbon, needed for living, growth and reproduction. The sources of energy can be light or chemical compounds; the sources of carbon can be of organic or inorganic origin. The terms ''aerobic respiration'', ''anaerobic respiration'' and ''fermentation'' (''substrate-level phosphorylation'') do not refer to primary nutritional groups, but simply reflect the different use of possible electron acceptors in particular organisms, such as in aerobic respiration, or nitrate (), sulfate () or fumarate in anaerobic respiration, or various metabolic intermediates in fermentation. Primary sources of energy ''Phototrophs'' absorb light in photoreceptors and transform it into chemical energy. ''Chemotrophs'' release chemical energy. The freed energy is stored as potential energy in ATP, carbohydrates, or proteins. Eventually, the energy is used for life p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemotroph
A chemotroph is an organism that obtains energy by the oxidation of electron donors in their environments. These molecules can be organic ( chemoorganotrophs) or inorganic ( chemolithotrophs). The chemotroph designation is in contrast to phototrophs, which use photons. Chemotrophs can be either autotrophic or heterotrophic. Chemotrophs can be found in areas where electron donors are present in high concentration, for instance around hydrothermal vents. Chemoautotroph Chemoautotrophs are autotrophic organisms that can rely on chemosynthesis, i.e. deriving biological energy from chemical reactions of environmental inorganic substrates and synthesizing all necessary organic compounds from carbon dioxide. Chemoautotrophs can use inorganic energy sources such as hydrogen sulfide, elemental sulfur, ferrous iron, molecular hydrogen, and ammonia or organic sources to produce energy. Most chemoautotrophs are prokaryotic extremophiles, bacteria, or archaea that live in o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemosynthesis
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 ferrous ions as a source of energy, rather than sunlight, as in photosynthesis. Chemotroph, Chemoautotrophs, organisms that obtain carbon from carbon dioxide through chemosynthesis, are phylogenetically diverse. Groups that include conspicuous or biogeochemically important taxa include the sulfur-oxidizing Gammaproteobacteria, the Campylobacterota, the Aquificota, 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 where hydrogen molecules (H2) are available, the energy available from the reaction between CO2 and H2 (leading to product ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sergei Winogradsky
Sergei Nikolaevich Winogradsky (; ; , Kyiv – 24 February 1953, Brie-Comte-Robert), also published under the name Sergius Winogradsky, was a Ukrainian and Russian microbiologist, ecologist and soil science, soil scientist who pioneered the Biogeochemical cycle, cycle-of-life concept. Winogradsky discovered the first known form of lithotrophy during his research with ''Beggiatoa'' in 1887. He reported that ''Beggiatoa'' oxidized hydrogen sulfide (H2S) as an energy source and formed intracellular sulfur droplets. This research provided the first example of lithotrophy, but not autotrophy. Born in the capital of present-day Ukraine, his legacy is also celebrated by this nation. His research on nitrifying bacteria would report the first known form of chemotroph, chemoautotrophy, showing how a lithotroph carbon fixation, fixes carbon dioxide (CO2) to make organic compounds. He is best known in school science as the inventor of the Winogradsky column technique for the study of sedim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrifying Bacteria
Nitrifying bacteria are chemolithotrophic organisms that include species of genera such as '' Nitrosomonas'', '' Nitrosococcus'', '' Nitrobacter'', '' Nitrospina'', '' Nitrospira'' and '' Nitrococcus''. These bacteria get their energy from the oxidation of inorganic nitrogen compounds. Types include ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB). Many species of nitrifying bacteria have complex internal membrane systems that are the location for key enzymes in nitrification: ammonia monooxygenase (which oxidizes ammonia to hydroxylamine), hydroxylamine oxidoreductase (which oxidizes hydroxylamine to nitric oxide - which is further oxidized to nitrite by a currently unidentified enzyme), and nitrite oxidoreductase (which oxidizes nitrite to nitrate). Ecology Nitrifying bacteria are present in distinct taxonomical groups and are found in highest numbers where considerable amounts of ammonia are present (such as areas with extensive protein decomposition ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria
Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit the air, soil, water, Hot spring, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria play a vital role in many stages of the nutrient cycle by recycling nutrients and the nitrogen fixation, fixation of nitrogen from the Earth's atmosphere, atmosphere. The nutrient cycle includes the decomposition of cadaver, dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microorganism
A microorganism, or microbe, is an organism of microscopic scale, microscopic size, which may exist in its unicellular organism, single-celled form or as a Colony (biology)#Microbial colonies, colony of cells. The possible existence of unseen microbial life was suspected from antiquity, with an early attestation in Jain literature authored in 6th-century BC India. The scientific study of microorganisms began with their observation under the microscope in the 1670s by Anton van Leeuwenhoek. In the 1850s, Louis Pasteur found that microorganisms caused food spoilage, debunking the theory of spontaneous generation. In the 1880s, Robert Koch discovered that microorganisms caused the diseases tuberculosis, cholera, diphtheria, and anthrax. Microorganisms are extremely diverse, representing most unicellular organisms in all three domains of life: two of the three domains, Archaea and Bacteria, only contain microorganisms. The third domain, Eukaryota, includes all multicellular o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Dioxide
Carbon dioxide is a chemical compound with the chemical formula . It is made up of molecules that each have one carbon atom covalent bond, covalently double bonded to two oxygen atoms. It is found in a gas state at room temperature and at normally-encountered concentrations it is odorless. As the source of carbon in the carbon cycle, atmospheric is the primary carbon source for life on Earth. In the air, carbon dioxide is transparent to visible light but absorbs infrared, infrared radiation, acting as a greenhouse gas. Carbon dioxide is soluble in water and is found in groundwater, lakes, ice caps, and seawater. It is a trace gas Carbon dioxide in Earth's atmosphere, in Earth's atmosphere at 421 parts per million (ppm), or about 0.042% (as of May 2022) having risen from pre-industrial levels of 280 ppm or about 0.028%. Burning fossil fuels is the main cause of these increased concentrations, which are the primary cause of climate change.IPCC (2022Summary for pol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inorganic Compound
An inorganic compound is typically a chemical compound that lacks carbon–hydrogen bondsthat is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as ''inorganic chemistry''. Inorganic compounds comprise most of the Earth's crust, although the compositions of the deep Mantle (geology), mantle remain active areas of investigation. All allotropes (structurally different pure forms of an element) and some simple carbon compounds are often considered inorganic. Examples include the allotropes of carbon (graphite, diamond, buckminsterfullerene, graphene, etc.), carbon monoxide , carbon dioxide , carbides, and salt (chemistry), salts of inorganic anions such as carbonates, cyanides, cyanates, thiocyanates, isothiocyanates, etc. Many of these are normal parts of mostly organic systems, including organisms; describing a chemical as inorganic does not necessarily mean that it cannot occur within life, living things. History ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Compounds
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element is therefore not a compound. A compound can be transformed into a different substance by a chemical reaction, which may involve interactions with other substances. In this process, bonds between atoms may be broken or new bonds formed or both. There are four major types of compounds, distinguished by how the constituent atoms are bonded together. Molecular compounds are held together by covalent bonds; ionic compounds are held together by ionic bonds; intermetallic compounds are held together by metallic bonds; coordination complexes are held together by coordinate covalent bonds. Non-stoichiometric compounds form a disputed marginal case. A chemical formula specifies the number of atoms of each element in a compound molecule, us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inorganic
An inorganic compound is typically a chemical compound that lacks carbon–hydrogen bondsthat is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemistry''. Inorganic compounds comprise most of the Earth's crust, although the compositions of the deep mantle remain active areas of investigation. All allotropes (structurally different pure forms of an element) and some simple carbon compounds are often considered inorganic. Examples include the allotropes of carbon (graphite, diamond, buckminsterfullerene, graphene, etc.), carbon monoxide , carbon dioxide , carbides, and salts of inorganic anions such as carbonates, cyanides, cyanates, thiocyanates, isothiocyanates, etc. Many of these are normal parts of mostly organic systems, including organisms; describing a chemical as inorganic does not necessarily mean that it cannot occur within living things. History Friedrich Wöhler's con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calvin Cycle
The Calvin cycle, light-independent reactions, bio synthetic phase, dark reactions, or photosynthetic carbon reduction (PCR) cycle of photosynthesis is a series of chemical reactions that convert carbon dioxide and hydrogen-carrier compounds into glucose. The Calvin cycle is present in all photosynthetic eukaryotes and also many photosynthetic bacteria. In plants, these reactions occur in the stroma, the fluid-filled region of a chloroplast outside the thylakoid membranes. These reactions take the products ( ATP and NADPH) of light-dependent reactions and perform further chemical processes on them. The Calvin cycle uses the chemical energy of ATP and the reducing power of NADPH from the light-dependent reactions to produce sugars for the plant to use. These substrates are used in a series of reduction-oxidation (redox) reactions to produce sugars in a step-wise process; there is no direct reaction that converts several molecules of to a sugar. There are three phases to the ligh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
