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Chlorosome
A chlorosome is a photosynthetic antenna complex found in green sulfur bacteria (GSB) and many green non-sulfur bacteria (GNsB), together known as green bacteria. They differ from other antenna complexes by their large size and lack of protein matrix supporting the photosynthetic pigments. Green sulfur bacteria are a group of organisms that generally live in extremely low-light environments, such as at depths of 100 metres in the Black Sea. The ability to capture light energy and rapidly deliver it to where it needs to go is essential to these bacteria, some of which see only a few photons of light per chlorophyll per day. To achieve this, the bacteria contain chlorosome structures, which contain up to 250,000 chlorophyll molecules. Chlorosomes are ellipsoidal bodies, in GSB their length varies from 100 to 200 nm, width of 50-100 nm and height of 15 – 30 nm, in GNsB the chlorosomes are somewhat smaller. Chlorosomes are a type of chromatophores that are fou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorosome By Hartmann
A chlorosome is a photosynthetic antenna complex found in green sulfur bacteria (GSB) and many green non-sulfur bacteria (GNsB), together known as green bacteria. They differ from other antenna complexes by their large size and lack of protein matrix supporting the photosynthetic pigments. Green sulfur bacteria are a group of organisms that generally live in extremely low-light environments, such as at depths of 100 metres in the Black Sea. The ability to capture light energy and rapidly deliver it to where it needs to go is essential to these bacteria, some of which see only a few photons of light per chlorophyll per day. To achieve this, the bacteria contain chlorosome structures, which contain up to 250,000 chlorophyll molecules. Chlorosomes are ellipsoidal bodies, in GSB their length varies from 100 to 200 nm, width of 50-100 nm and height of 15 – 30 nm, in GNsB the chlorosomes are somewhat smaller. Chlorosomes are a type of chromatophores that are found i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Sulfur Bacteria
The green sulfur bacteria are a phylum, Chlorobiota, of obligately anaerobic photoautotrophic bacteria that metabolize sulfur. Green sulfur bacteria are nonmotile (except ''Chloroherpeton thalassium'', which may glide) and capable of anoxygenic photosynthesis. They live in anaerobic aquatic environments. In contrast to plants, green sulfur bacteria mainly use sulfide ions as electron donors. They are autotrophs that utilize the reverse tricarboxylic acid cycle to perform carbon fixation. They are also mixotrophs and reduce nitrogen. Characteristics Green sulfur bacteria are gram-negative rod or spherical shaped bacteria. Some types of green sulfur bacteria have gas vacuoles that allow for movement. They are photolithoautotrophs, and use light energy and reduced sulfur compounds as the electron source. Electron donors include , , S. The major photosynthetic pigment in these bacteria is Bacteriochlorophylls ''c'' or ''d'' in green species and ''e'' in brown species, and is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antenna Complex
In biology, a light-harvesting complex or LHC is an aggregate consisting of proteins bound with chromophores (chlorophylls and carotenoids) that play a key role in photosynthesis. LHCs are arrayed around photosynthetic reaction centers in both plants and photosynthetic bacteria and collect more of the incoming light than would be captured by the reaction centers alone. The light captured by the chromophores excites molecules from their ground states to (short-lived) higher-energy states, known as the excited states. This energy is then focused toward the reaction centers by Förster resonance energy transfer. Light-harvesting complexes are found in a wide variety among the different photosynthetic species, with no homology among the major groups. Function Photosynthesis is a process where light is absorbed or harvested by pigment protein complexes which are able to turn sunlight into chemical energy. In this process, a molecule of the pigment protein absorbs a photon of sunlig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteriochlorophyll
Bacteriochlorophylls (BChl) are photosynthetic pigments that occur in various phototrophic bacteria. They were discovered by C. B. van Niel in 1932. They are related to chlorophylls, which are the primary pigments in plants, algae, and cyanobacteria. Organisms that contain bacteriochlorophyll conduct photosynthesis to sustain their energy requirements, but the process is anoxygenic and does not produce oxygen as a byproduct. They use wavelengths of light not absorbed by plants or cyanobacteria. Replacement of with protons gives bacteriophaeophytin (BPh), the phaeophytin form. BacterioChlorophyll a.svg, bacteriochlorophyll ''a'' BacterioChlorophyll b.svg, bacteriochlorophyll ''b'' BacterioChlorophyll c.svg, bacteriochlorophyll ''c'' BacterioChlorophyll d.svg, bacteriochlorophyll ''d'' BacterioChlorophyll e.svg, bacteriochlorophyll ''e'' Bacteriochlorophyll f.svg, bacteriochlorophyll ''f'' BacterioChlorophyll g.svg, bacteriochlorophyll ''g'' Structure Bacteriochlorophyll ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromatophore (bacteria)
In some forms of photosynthetic bacteria, a chromatophore is a pigmented(coloured), membrane-associated vesicle used to perform photosynthesis. They contain different coloured pigments. Chromatophores contain bacteriochlorophyll pigments and carotenoids. In purple bacteria, such as '' Rhodospirillum rubrum'', the light-harvesting proteins are intrinsic to the chromatophore membranes. However, in green sulfur bacteria, they are arranged in specialised antenna complexes called chlorosomes. References Photosynthesis Organelles {{bacteria-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Non-sulfur Bacteria
Chloroflexales is an order of bacteria in the class Chloroflexia. The clade is also known as filamentous anoxygenic phototrophic bacteria (FAP), as the order contains phototrophs that do not produce oxygen. These bacteria are facultative aerobic. They generally use chemotrophy when oxygen is present and switch to light-derived energy when otherwise. Most species are heterotrophs, but a few are capable of photoautotrophy. The order can be divided into two suborders. Chloroflexineae ("Green FAP", "green non-sulfur bacteria") is the better-known one. This suborder uses chlorosomes, a specialized antenna complex, to pass light energy to the reaction center. Roseiflexineae ("Red FAP") on the other hand has no such ability. The named colors are not absolute, as growth conditions such as oxygen concentration will make a green FAP appear green, brown, or reddish-orange by inducing changes in pigment composition. Classification The currently accepted taxonomy is based on the List of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteriochlorophyll
Bacteriochlorophylls (BChl) are photosynthetic pigments that occur in various phototrophic bacteria. They were discovered by C. B. van Niel in 1932. They are related to chlorophylls, which are the primary pigments in plants, algae, and cyanobacteria. Organisms that contain bacteriochlorophyll conduct photosynthesis to sustain their energy requirements, but the process is anoxygenic and does not produce oxygen as a byproduct. They use wavelengths of light not absorbed by plants or cyanobacteria. Replacement of with protons gives bacteriophaeophytin (BPh), the phaeophytin form. BacterioChlorophyll a.svg, bacteriochlorophyll ''a'' BacterioChlorophyll b.svg, bacteriochlorophyll ''b'' BacterioChlorophyll c.svg, bacteriochlorophyll ''c'' BacterioChlorophyll d.svg, bacteriochlorophyll ''d'' BacterioChlorophyll e.svg, bacteriochlorophyll ''e'' Bacteriochlorophyll f.svg, bacteriochlorophyll ''f'' BacterioChlorophyll g.svg, bacteriochlorophyll ''g'' Structure Bacteriochlorophyll ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolution
Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, resulting in certain characteristics becoming more or less common within a population over successive generations. The process of evolution has given rise to biodiversity at every level of biological organisation. The scientific theory of evolution by natural selection was conceived independently by two British naturalists, Charles Darwin and Alfred Russel Wallace, in the mid-19th century as an explanation for why organisms are adapted to their physical and biological environments. The theory was first set out in detail in Darwin's book ''On the Origin of Species''. Evolution by natural selection is established by observable facts about living organisms: (1) more offspring are often produced than can possibly survive; (2) phenotypic variatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Modelling
Molecular modelling encompasses all methods, theoretical and computational, used to model or mimic the behaviour of molecules. The methods are used in the fields of computational chemistry, drug design, computational biology and materials science to study molecular systems ranging from small chemical systems to large biological molecules and material assemblies. The simplest calculations can be performed by hand, but inevitably computers are required to perform molecular modelling of any reasonably sized system. The common feature of molecular modelling methods is the atomistic level description of the molecular systems. This may include treating atoms as the smallest individual unit (a molecular mechanics approach), or explicitly modelling protons and neutrons with its quarks, anti-quarks and gluons and electrons with its photons (a quantum chemistry approach). Molecular mechanics Molecular mechanics is one aspect of molecular modelling, as it involves the use of classical mec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Farnesol
Farnesol is a natural 15-carbon organic compound which is an acyclic sesquiterpene alcohol. Under standard conditions, it is a colorless liquid. It is hydrophobic, and thus insoluble in water, but miscible with oils. As the pyrophosphate ester, farnesol is a precursor to many terpenes and terpenoids. Uses Farnesol is present in many essential oils such as citronella oil, citronella, neroli, cyclamen, lemon grass, tuberose, rose, musk, balsam, and Tolu balsam, tolu. It is used in perfumery to emphasize the odors of sweet, floral perfumes. It enhances perfume scent by acting as a co-solvent that regulates the volatility of the odorants. It is especially used in lilac and peony perfumes. Farnesol and its ester derivatives are important organic synthesis, precursors for a variety of other compounds used as fragrances and vitamins. Cosmetics Farnesol is used as a deodorant in cosmetic products. Farnesol is subject to restrictions on its use in perfumery, because some people may beco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
