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Proton-pumping Pyrophosphatase
Members of the H+, Na+-translocating Pyrophosphatase (M+''-PPase)'' FamilyTC# 3.A.10 are found in the vacuolar (tonoplast) membranes of higher plants, algae, and protozoa, and in both bacteria and archaea. They are therefore ancient enzymes. Two types of inorganic diphosphatase, very different in terms of both amino acid sequence and structure, have been characterised to date: soluble and transmembrane proton-pumping pyrophosphatases (sPPases and H(+)-PPases, respectively). sPPases are ubiquitous proteins that hydrolyse pyrophosphate to release heat, whereas H+-PPases, so far unidentified in animal and fungal cells, couple the energy of PPi hydrolysis to proton movement across biological membranes. The latter type is represented by this group of proteins. H+-PPases vacuolar-type inorganic pyrophosphatases (V-PPase) or pyrophosphate-energised vacuolar membrane proton pumps. In plants, vacuoles contain two enzymes for acidifying the interior of the vacuole, the V-ATPase and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vacuole
A vacuole () is a membrane-bound organelle which is present in plant and fungal cells and some protist, animal, and bacterial cells. Vacuoles are essentially enclosed compartments which are filled with water containing inorganic and organic molecules including enzymes in solution, though in certain cases they may contain solids which have been engulfed. Vacuoles are formed by the fusion of multiple membrane vesicles and are effectively just larger forms of these. The organelle has no basic shape or size; its structure varies according to the requirements of the cell. Discovery Contractile vacuoles ("stars") were first observed by Spallanzani (1776) in protozoa, although mistaken for respiratory organs. Dujardin (1841) named these "stars" as ''vacuoles''. In 1842, Schleiden applied the term for plant cells, to distinguish the structure with cell sap from the rest of the protoplasm. In 1885, de Vries named the vacuole membrane as tonoplast. Function The function and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vacuolar
A vacuole () is a membrane-bound organelle which is present in Plant cell, plant and Fungus, fungal Cell (biology), cells and some protist, animal, and bacterial cells. Vacuoles are essentially enclosed compartments which are filled with water containing inorganic and organic molecules including enzymes in Solutes, solution, though in certain cases they may contain solids which have been engulfed. Vacuoles are formed by the fusion of multiple membrane Vesicle (biology), vesicles and are effectively just larger forms of these. The organelle has no basic shape or size; its structure varies according to the requirements of the cell. Discovery Contractile vacuoles ("stars") were first observed by Spallanzani (1776) in protozoa, although mistaken for respiratory organs. Félix Dujardin, Dujardin (1841) named these "stars" as ''vacuoles''. In 1842, Matthias Jakob Schleiden, Schleiden applied the term for plant cells, to distinguish the structure with cell sap from the rest of the prot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Streptomyces Coelicolor
''Streptomyces albidoflavus'' is a bacterium species from the genus of ''Streptomyces'' which has been isolated from soil from Poland. ''Streptomyces albidoflavus'' produces dibutyl phthalate and streptothricins. Small noncoding RNA Bacterial small RNAs are involved in post-transcriptional regulation. Using deep sequencing ''S. albidoflavus'' transcriptome was analysed at the end of exponential growth. 63 small RNAs were identified. Expression of 11 of them was confirmed by Northern blot. The sRNAs were shown to be only present in ''Streptomyces'' species. sRNA scr4677 (''Streptomyces coelicolor'' sRNA 4677) is located in the intergenic region between anti-sigma factor ''SCO4677'' gene and a putative regulatory protein gene ''SCO4676''. ''scr4677'' expression requires the ''SCO4677'' activity and ''scr4677'' sRNA itself seem to affect the levels of the ''SCO4676''-associated transcripts. Targets of two of ''S. albidoflavus'' noncoding RNAs have been identified. Noncoding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Dimer
In biochemistry, a protein dimer is a macromolecular complex formed by two protein monomers, or single proteins, which are usually non-covalently bound. Many macromolecules, such as proteins or nucleic acids, form dimers. The word ''dimer'' has roots meaning "two parts", ''di-'' + '' -mer''. A protein dimer is a type of protein quaternary structure. A protein homodimer is formed by two identical proteins. A protein heterodimer is formed by two different proteins. Most protein dimers in biochemistry are not connected by covalent bonds. An example of a non-covalent heterodimer is the enzyme reverse transcriptase, which is composed of two different amino acid chains. An exception is dimers that are linked by disulfide bridges such as the homodimeric protein NEMO. Some proteins contain specialized domains to ensure dimerization (dimerization domains) and specificity. The G protein-coupled cannabinoid receptors have the ability to form both homo- and heterodimers with sev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proton Motive Force
Chemiosmosis is the movement of ions across a semipermeable membrane bound structure, down their electrochemical gradient. An important example is the formation of adenosine triphosphate (ATP) by the movement of hydrogen ions (H+) across a membrane during cellular respiration or photosynthesis. Hydrogen ions, or protons, will diffuse from a region of high proton concentration to a region of lower proton concentration, and an electrochemical concentration gradient of protons across a membrane can be harnessed to make ATP. This process is related to osmosis, the movement of water across a selective membrane, which is why it is called "chemiosmosis". ATP synthase is the enzyme that makes ATP by chemiosmosis. It allows protons to pass through the membrane and uses the free energy difference to phosphorylate adenosine diphosphate (ADP), making ATP. The generation of ATP by chemiosmosis occurs in mitochondria and chloroplasts, as well as in most bacteria and archaea. For in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desulfuromonas Acetoxidans
''Desulfuromonas acetoxidans'' is a species of bacteria. It is strictly anaerobic, rod-shaped, laterally flagellated and Gram-negative Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wa .... It is unable to ferment organic substances; it obtains energy for growth by anaerobic sulfur respiration. References Further reading * * * External links Geobacter Project Desulfuromonadales< ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clostridium Tetani
''Clostridium tetani'' is a common soil bacterium and the causative agent of tetanus. Vegetative cells of ''Clostridium tetani'' are usually rod-shaped and up to 2.5 μm long, but they become enlarged and tennis racket- or drumstick-shaped when forming spores. ''C. tetani'' spores are extremely hardy and can be found globally in soil or in the gastrointestinal tract of animals. If inoculated into a wound, ''C. tetani'' can grow and produce a potent toxin, tetanospasmin, which interferes with motor neurons, causing tetanus. The toxin's action can be prevented with tetanus toxoid vaccines, which are often administered to children worldwide. Characteristics ''Clostridium tetani'' is a rod-shaped, Gram-positive bacterium, typically up to 0.5 μm wide and 2.5 μm long. It is motile by way of various flagella that surround its body. ''C. tetani'' cannot grow in the presence of oxygen. It grows best at temperatures ranging from 33 to 37°C. Upon exposure to various conditions, ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anaerostipes Caccae
''Anaerostipes caccae'' is a Gram-variable, anaerobic saccharolytic, rod-shaped butyrate-producing and acetate and lactate-utilising bacterium from the genus of Anaerostipes ''Anaerostipes'' is a Gram positive and anaerobic bacterial genus from the family of Lachnospiraceae. ''Anaerostipes'' occurs in the human gut. ''Anaerostipes'' may protect against colon cancer in humans by producing butyric acid Butyric aci ... which has been isolated from human faeces. References Further reading * * * * External linksType strain of ''Anaerostipes caccae'' at Bac''Dive'' - the Bacterial Diversity Metadatabase Lachnospiraceae Bacteria described in 2002 {{Firmicutes-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrophosphatase
Pyrophosphatases, also known as diphosphatases, are acid anhydride hydrolases that act upon diphosphate bonds. Examples include: * Inorganic pyrophosphatase, which acts upon the free pyrophosphate ion * Tobacco acid pyrophosphatase, which catalyses the hydrolysis of a phosphoric ester * Various organic pyrophosphatases, which act upon organic molecules with the pyrophosphate group (but excluding triphosphatases that act on the final bond): ** Thiamine pyrophosphatase In enzymology, a nucleoside-diphosphatase () is an enzyme that catalyzes the chemical reaction :a nucleoside diphosphate + H2O \rightleftharpoons a nucleotide + phosphate Thus, the two substrates of this enzyme are nucleoside diphosphate and ... See also * References External links * EC 3.6.1 {{3.6-enzyme-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanosarcina
''Methanosarcina'' is a genus of euryarchaeote archaea that produce methane. These single-celled organisms are known as anaerobic methanogens that produce methane using all three metabolic pathways for methanogenesis. They live in diverse environments where they can remain safe from the effects of oxygen, whether on the earth's surface, in groundwater, in deep sea vents, and in animal digestive tracts. ''Methanosarcina'' grow in colonies. The amino acid pyrrolysine was first discovered in a ''Methanosarcina'' species, '' M. barkeri''. Primitive versions of hemoglobin have been found in ''M. acetivorans'', suggesting the microbe or an ancestor of it may have played a crucial role in the evolution of life on Earth. Species of ''Methanosarcina'' are also noted for unusually large genomes. ''M. acetivorans'' has the largest known genome of any archaeon. According to a theory published in 2014, ''Methanosarcina'' may have been largely responsible for the largest extinction eve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium
Potassium is the chemical element with the symbol K (from Neo-Latin '' kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure. It was first isolated from potash, the ashes of plants, from which its name derives. In the periodic table, potassium is one of the alkali metals, all of which have a single valence electron in the outer electron shell, that is easily removed to create an ion with a positive charge – a cation, that combines with anions to form salts. Potassium in nature occurs only in ionic salts. Elemental potassium reacts vigorously with water, generating sufficient heat to ignite hydrogen emitted in the reaction, and burning with a lilac- colored flame. It is found dissolved in sea water (which is 0.04% potassium by weight), and occurs in many minerals such as orth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biochemistry
Biochemistry or biological chemistry is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and biology, biochemistry may be divided into three fields: structural biology, enzymology and metabolism. Over the last decades of the 20th century, biochemistry has become successful at explaining living processes through these three disciplines. Almost all areas of the life sciences are being uncovered and developed through biochemical methodology and research.Voet (2005), p. 3. Biochemistry focuses on understanding the chemical basis which allows biological molecules to give rise to the processes that occur within living cells and between cells, Karp (2009), p. 2. in turn relating greatly to the understanding of tissues and organs, as well as organism structure and function. Miller (2012). p. 62. Biochemistry is closely related to molecular biology, which is the study of the molecular mechanisms of biological phenom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
