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Peroxisome
A peroxisome () is a membrane-bound organelle, a type of microbody, found in the cytoplasm of virtually all eukaryotic cells. Peroxisomes are oxidative organelles. Frequently, molecular oxygen serves as a co-substrate, from which hydrogen peroxide (H2O2) is then formed. Peroxisomes owe their name to hydrogen peroxide-generating and scavenging activities. They perform key roles in lipid metabolism and the redox, reduction of reactive oxygen species. Peroxisomes are involved in the catabolism of very long chain fatty acids, branched chain fatty acids, bile acid intermediates (in the liver), D-amino acids, and polyamines. Peroxisomes also play a role in the biosynthesis of plasmalogens: ether phospholipids critical for the normal function of mammalian brains and lungs. Peroxisomes contain approximately 10% of the total activity of two enzymes (Glucose-6-phosphate dehydrogenase and Phosphogluconate dehydrogenase, 6-Phosphogluconate dehydrogenase) in the pentose phosphate pathway, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peroxisome In Rat Neonatal Cardiomyocyte
A peroxisome () is a membrane-bound organelle, a type of microbody, found in the cytoplasm of virtually all eukaryotic cells. Peroxisomes are oxidative organelles. Frequently, molecular oxygen serves as a co-substrate, from which hydrogen peroxide (H2O2) is then formed. Peroxisomes owe their name to hydrogen peroxide-generating and scavenging activities. They perform key roles in lipid metabolism and the reduction of reactive oxygen species. Peroxisomes are involved in the catabolism of very long chain fatty acids, branched chain fatty acids, bile acid intermediates (in the liver), D-amino acids, and polyamines. Peroxisomes also play a role in the biosynthesis of plasmalogens: ether phospholipids critical for the normal function of mammalian brains and lungs. Peroxisomes contain approximately 10% of the total activity of two enzymes (Glucose-6-phosphate dehydrogenase and 6-Phosphogluconate dehydrogenase) in the pentose phosphate pathway, which is important for ener ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microbody
A microbody (or cytosome) is a type of organelle that is found in the cells of plants, protozoa, and animals. Organelles in the microbody family include peroxisomes, glyoxysomes, glycosomes and hydrogenosomes. In vertebrates, microbodies are especially prevalent in the liver and kidney. Many membrane bound vesicles called microbodies that contain various enzymes, are present in both plant and animal cells. Structure Microbodies are different type of bodies present in the cytosol, also known as cytosomes. A microbody is usually a vesicle with a spherical shape, ranging from 0.2-1.5 micrometers in diameter."Microbodies." Molecular Biology of Plant Cells. Ed. H. Smith. N.p.: University of California, 1978. 136-54. Print. Microbodies are found in the cytoplasm of a cell, but they are only visible with the use of an electron microscope. They are surrounded by a single phospholipid bilayer membrane and they contain a matrix of intracellular material including enzymes and other prot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycosome
The glycosome is a membrane A membrane is a selective barrier; it allows some things to pass through but stops others. Such things may be molecules, ions, or other small particles. Membranes can be generally classified into synthetic membranes and biological membranes. Bi ...-enclosed organelle that contains the glycolysis, glycolytic enzymes. The term was first used by Scott and Still in 1968 after they realized that the glycogen in the cell was not static but rather a dynamic molecule. It is found in a few species of protozoa including the Kinetoplastida which include the suborders Trypanosomatida and Bodonina, most notably in the human pathogenic trypanosomes, which can cause African trypanosomiasis, sleeping sickness, Chagas's disease, and leishmaniasis. The organelle is bounded by a single membrane and contains a dense proteinaceous matrix. It is believed to have evolved from the peroxisome. This has been verified by work done on Leishmania genetics. The glycosome is curre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Peroxide
Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscosity, viscous than Properties of water, water. It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%–6% by weight) in water for consumer use and in higher concentrations for industrial use. Concentrated hydrogen peroxide, or "high-test peroxide", decomposes explosively when heated and has been used as both a monopropellant and an oxidizer in rocketry. Hydrogen peroxide is a reactive oxygen species and the simplest peroxide, a compound having an oxygen–oxygen single bond. It decomposes slowly into water and elemental oxygen when exposed to light, and rapidly in the presence of organic or reactive compounds. It is typically stored with a Stabilizer (chemistry), stabilizer in a weakly acidic solution in an opaque bottle. Hydrogen peroxide is found in biological systems including the human body. Enzymes that u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasmalogen
Plasmalogens are a class of glycerophospholipid with a plasmenyl group linked to a lipid at the sn-1 position of the glycerol backbone. Plasmalogens are found in multiple domains of life, including Mammal, mammals, Invertebrate, invertebrates, protozoa, and Anaerobic organism, anaerobic bacteria. They are commonly found in cell membranes in the nervous system, nervous, immune system, immune, and cardiovascular systems. In humans, lower levels of plasmalogens are studied in relation to some diseases. Plasmalogens are also associated with adaptations to extreme environments in non-human organisms. Structure Glycerophospholipids of biochemical relevance are divided into three subclasses based on the substitution present at the Glycerophospholipid#Nomenclature and stereochemistry, sn-1 position of the glycerol backbone: acyl_group, acyl, alkyl_group, alkyl and alkenyl_group, alkenyl. Of these, the alkyl and alkenyl moiety in each case form an ether bond, which makes for two types o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cholesterol
Cholesterol is the principal sterol of all higher animals, distributed in body Tissue (biology), tissues, especially the brain and spinal cord, and in Animal fat, animal fats and oils. Cholesterol is biosynthesis, biosynthesized by all animal Cell (biology)#Eukaryotic cells, cells and is an essential structural and cholesterol signaling, signaling component of animal cell membranes. In vertebrates, hepatocyte, hepatic cells typically produce the greatest amounts. In the brain, astrocytes produce cholesterol and transport it to neurons. It is absent among prokaryotes (bacteria and archaea), although there are some exceptions, such as ''Mycoplasma'', which require cholesterol for growth. Cholesterol also serves as a Precursor (chemistry), precursor for the biosynthesis of steroid hormones, bile acid and vitamin D. Elevated levels of cholesterol in the blood, especially when bound to low-density lipoprotein (LDL, often referred to as "bad cholesterol"), may increase the risk of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphogluconate Dehydrogenase
6-Phosphogluconate dehydrogenase (6PGD) is an enzyme in the pentose phosphate pathway. It forms ribulose 5-phosphate from 6-phosphogluconate: :6-phospho-D-gluconate + NAD(P)+ \rightleftharpoons D-Ribulose 5-phosphate + CO2 + NAD(P)H + H+ It is an oxidative carboxylase that catalyses the oxidative decarboxylation of 6-phosphogluconate into ribulose 5-phosphate in the presence of NADP. This reaction is a component of the hexose mono-phosphate shunt and pentose phosphate pathways (PPP). Prokaryotic and eukaryotic 6PGD are proteins of about 470 amino acids whose sequences are highly conserved. The protein is a homodimer in which the monomers act independently: each contains a large, mainly alpha-helical domain and a smaller beta-alpha-beta domain, containing a mixed parallel and anti-parallel 6-stranded beta sheet. NADP is bound in a cleft in the small domain, the substrate binding in an adjacent pocket. Biotechnological significance Recently, 6PGD was demonstrated to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentose Phosphate Pathway
The pentose phosphate pathway (also called the phosphogluconate pathway and the hexose monophosphate shunt or HMP shunt) is a metabolic pathway parallel to glycolysis. It generates NADPH and pentoses (five-carbon sugars) as well as ribose 5-phosphate, a precursor for the synthesis of nucleotides. While the pentose phosphate pathway does involve oxidation of glucose, its primary role is anabolic rather than catabolic. The pathway is especially important in red blood cells (erythrocytes). The reactions of the pathway were elucidated in the early 1950s by Bernard Horecker and co-workers. There are two distinct phases in the pathway. The first is the oxidative phase, in which NADPH is generated, and the second is the non-oxidative synthesis of five-carbon sugars. For most organisms, the pentose phosphate pathway takes place in the cytosol; in plants, most steps take place in plastids. Like glycolysis, the pentose phosphate pathway appears to have a very ancient evolutionary ori ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isoprenoid
The terpenoids, also known as isoprenoids, are a class of naturally occurring organic chemicals derived from the 5-carbon compound isoprene and its derivatives called terpenes, diterpenes, etc. While sometimes used interchangeably with "terpenes", terpenoids contain additional functional groups, usually containing oxygen. When combined with the hydrocarbon terpenes, terpenoids comprise about 80,000 compounds. They are the largest class of plant secondary metabolites, representing about 60% of known natural products. Many terpenoids have substantial pharmacological bioactivity and are therefore of interest to medicinal chemists. Plant terpenoids are used for their aromatic qualities and play a role in traditional herbal remedies. Terpenoids contribute to the scent of eucalyptus, the flavors of cinnamon, cloves, and ginger, the yellow color in sunflowers, and the red color in tomatoes. Well-known terpenoids include citral, menthol, camphor, salvinorin A in the plant '' S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycolysis
Glycolysis is the metabolic pathway that converts glucose () into pyruvic acid, pyruvate and, in most organisms, occurs in the liquid part of cells (the cytosol). The Thermodynamic free energy, free energy released in this process is used to form the high-energy molecules adenosine triphosphate (ATP) and NADH, reduced nicotinamide adenine dinucleotide (NADH). Glycolysis is a sequence of ten reactions catalyzed by enzymes. The wide occurrence of glycolysis in other species indicates that it is an ancient metabolic pathway. Indeed, the reactions that make up glycolysis and its parallel pathway, the pentose phosphate pathway, can occur in the Great Oxygenation Event, oxygen-free conditions of the Archean oceans, also in the absence of enzymes, catalyzed by metal ions, meaning this is a plausible prebiotic pathway for abiogenesis. The most common type of glycolysis is the ''Embden–Meyerhof–Parnas (EMP) pathway'', which was discovered by Gustav Embden, Otto Meyerhof, and Jakub Kar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glyoxylate Cycle
The glyoxylate cycle, a variation of the tricarboxylic acid cycle, is an anabolic pathway occurring in plants, bacteria, protists, and fungi. The glyoxylate cycle centers on the conversion of acetyl-CoA to succinate for the synthesis of carbohydrates. In microorganisms, the glyoxylate cycle allows cells to use two carbons (C2 compounds), such as acetate, to satisfy cellular carbon requirements when simple sugars such as glucose or fructose are not available. The cycle is generally assumed to be absent in animals, with the exception of nematodes at the early stages of embryogenesis. In recent years, however, the detection of malate synthase (MS) and isocitrate lyase (ICL), key enzymes involved in the glyoxylate cycle, in some animal tissue has raised questions regarding the evolutionary relationship of enzymes in bacteria and animals and suggests that animals encode alternative enzymes of the cycle that differ in function from known MS and ICL in non-metazoan species. Plants as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
