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Scalarin
Scalarin (PsSC) is the most abundant perivitellin of the perivitelline fluid from ''Pomacea scalaris'' eggs. This glyco-lipo-caroteno protein is an approx. 380 kDa multimer combining multiple copies of six different 24-35 kDa subunits. As part of the petivitelline fluid, PsSC is probably playing a role as a nutrient source for the developing embryo in ''Pomacea scalaris'' eggs. As its orthologous ovorubin and PmPV1, this protein carries and stabilizes carotenoid pigments. As a consequence, this perivitellin absorbs light throughout the visible range, a characteristic related to a photoprotective role in these aerially deposited eggs. The presence on its structure of carotenoid pigments is also associated with protective antioxidative properties. Like most other studied perivitellins from ''Pomacea'' snails, PsSC is highly stable in a wide range of pH values and withstands gastrointestinal digestion, characteristics associated with an antinutritive defense system that deters ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perivitellins
Perivitellins are egg proteins found in the perivitelline fluid of many gastropods. They are multifunctional complexes providing the developing embryo with nutrition, protection from the environment, and defense against predators. Despite the central role perivitellins play in reproduction and development, there is little information about their role in gastropod Molluscs. Most studies of perivitellins have been performed in eggs of Ampullaridae, a family of freshwater snails (Caenogastropoda), notably the ''Pomacea'' genus, mostly those of ''Pomacea canaliculata'', ''Pomacea scalaris'' and ''Pomacea maculata''. Synthesis Perivitellins are almost exclusively synthesized in the albumen gland (also known as albumen gland-capsule gland complex or uterine gland), an accessory gland from the female reproductive system of gastropods. This has been experimentally confirmed for the perivitellins ovorubin (PcOvo) and PcPV2, which were only found in the albumen gland with no extra-gland ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pomacea
''Pomacea'' is a genus of freshwater snails with gills and an operculum, aquatic gastropod mollusks in the family Ampullariidae, the apple snails. The genus is native to the Americas; most species in this genus are restricted to South America. in the aquarium trade these snails are sometimes called ''Pomacea'' or incorrectly ''Ampullarius'', and in English as "olormystery snail" or "apple snail". Some species have been introduced outside their native range and are considered invasive because of their voracious appetite for plants. Because of this, imports involving this genus are restricted in some regions (including the United States) and are entirely banned in others (including the EU).Dawes, J. (14 January 2013). International Waters: EU Finally Bans Apple Snail Imports.'' Retrieved 4 June 2014 Species Species in the genus ''Pomacea'' include: subgenus ''Effusa'' Jousseaume, 1889 * ''Pomacea baeri'' (Dautzenberg, 1902) * ''Pomacea glauca'' (Linné, 1758) * ''Pomacea q ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gram-negative Bacteria
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 wall sandwiched between an inner cytoplasmic cell membrane and a bacterial outer membrane. Gram-negative bacteria are found in virtually all environments on Earth that support life. The gram-negative bacteria include the model organism ''Escherichia coli'', as well as many pathogenic bacteria, such as ''Pseudomonas aeruginosa'', '' Chlamydia trachomatis'', and ''Yersinia pestis''. They are a significant medical challenge as their outer membrane protects them from many antibiotics (including penicillin), detergents that would normally damage the inner cell membrane, and lysozyme, an antimicrobial enzyme produced by animals that forms part of the innate immune system. Additionally, the outer leaflet of this membrane comprises a complex lipopol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Blood Cell
Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek ''erythros'' for "red" and ''kytos'' for "hollow vessel", with ''-cyte'' translated as "cell" in modern usage), are the most common type of blood cell and the vertebrate's principal means of delivering oxygen (O2) to the body tissues—via blood flow through the circulatory system. RBCs take up oxygen in the lungs, or in fish the gills, and release it into tissues while squeezing through the body's capillaries. The cytoplasm of a red blood cell is rich in hemoglobin, an iron-containing biomolecule that can bind oxygen and is responsible for the red color of the cells and the blood. Each human red blood cell contains approximately 270 million hemoglobin molecules. The cell membrane is composed of proteins and lipids, and this structure provides properties essential for physiolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ABO Blood Group System
The ABO blood group system is used to denote the presence of one, both, or neither of the A and B antigens on erythrocytes. For human blood transfusions, it is the most important of the 43 different blood type (or group) classification systems currently recognized by the International Society of Blood Transfusions (ISBT) as of June 2021. A mismatch (very rare in modern medicine) in this, or any other serotype, can cause a potentially fatal adverse reaction after a transfusion, or an unwanted immune response to an organ transplant. The associated anti-A and anti-B antibodies are usually IgM antibodies, produced in the first years of life by sensitization to environmental substances such as food, bacteria, and viruses. The ABO blood types were discovered by Karl Landsteiner in 1901; he received the Nobel Prize in Physiology or Medicine in 1930 for this discovery. ABO blood types are also present in other primates such as apes and Old World monkeys. History Discovery The ABO ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ganglioside
A ganglioside is a molecule composed of a glycosphingolipid (ceramide and oligosaccharide) with one or more sialic acids (e.g. ''N''-acetylneuraminic acid, NANA) linked on the sugar chain. NeuNAc, an acetylated derivative of the carbohydrate sialic acid, makes the head groups of gangliosides anionic at pH 7, which distinguishes them from globosides. The name ''ganglioside'' was first applied by the German scientist Ernst Klenk in 1942 to lipids newly isolated from ganglion cells of the brain. More than 60 gangliosides are known, which differ from each other mainly in the position and number of NANA residues. It is a component of the cell plasma membrane that modulates cell signal transduction events, and appears to concentrate in lipid rafts. Recently, gangliosides have been found to be highly important molecules in immunology. Natural and semisynthetic gangliosides are considered possible therapeutics for neurodegenerative disorders. Location Gangliosides are present and c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycosphingolipid
Glycosphingolipids are a subtype of glycolipids containing the amino alcohol sphingosine. They may be considered as sphingolipids with an attached carbohydrate. Glycosphingolipids are a group of lipids (more specifically, sphingolipids) and are a part of the cell membrane. They consist of a hydrophobic ceramide part and a glycosidically bound carbohydrate part. This oligosaccharide content remains on the outside of the cell membrane where it is important for biological processes such as cell adhesion or cell–cell interactions. Glycosphingolipids play also important role in oncogenesis and ontogenesis. Classification In general, glycosphingolipids can be categorized into two groups: neutral glycosphingolipids (also called glycosphingolipids) and negatively charged glycosphingolipids. The latter can be distinguished again by means of the charge carrier. While in gangliosides sialic acids are found, sulfatides have a sulfate group. The structural similarity of most glycolipids is t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lectin
Lectins are carbohydrate-binding proteins that are highly specific for sugar groups that are part of other molecules, so cause agglutination of particular cells or precipitation of glycoconjugates and polysaccharides. Lectins have a role in recognition at the cellular and molecular level and play numerous roles in biological recognition phenomena involving cells, carbohydrates, and proteins. Lectins also mediate attachment and binding of bacteria, viruses, and fungi to their intended targets. Lectins are ubiquitous in nature and are found in many foods. Some foods, such as beans and grains, need to be cooked, fermented or sprouted to reduce lectin content. Some lectins are beneficial, such as CLEC11A, which promotes bone growth, while others may be powerful toxins such as ricin. Lectins may be disabled by specific mono- and oligosaccharides, which bind to ingested lectins from grains, legumes, nightshade plants, and dairy; binding can prevent their attachment to the carbohy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perivitellins
Perivitellins are egg proteins found in the perivitelline fluid of many gastropods. They are multifunctional complexes providing the developing embryo with nutrition, protection from the environment, and defense against predators. Despite the central role perivitellins play in reproduction and development, there is little information about their role in gastropod Molluscs. Most studies of perivitellins have been performed in eggs of Ampullaridae, a family of freshwater snails (Caenogastropoda), notably the ''Pomacea'' genus, mostly those of ''Pomacea canaliculata'', ''Pomacea scalaris'' and ''Pomacea maculata''. Synthesis Perivitellins are almost exclusively synthesized in the albumen gland (also known as albumen gland-capsule gland complex or uterine gland), an accessory gland from the female reproductive system of gastropods. This has been experimentally confirmed for the perivitellins ovorubin (PcOvo) and PcPV2, which were only found in the albumen gland with no extra-gland ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perivitelline Fluid
The perivitelline fluid is an extracellular fluid found in the eggs of most gastropods and constitutes the main source of nutrition and defense for their embryos. It replaces the egg yolk of other animals, which in snail eggs is reduced to non-nutritive proteinaceous granules with putative enzymatic function. During embryonic development the perivitelline fluid is ingested macropinocytotically by the embryos and the resulting phagosomes fuse with β-granules containing hydrolytic enzymes, which digest the perivitelline fluid components. Origin The perivitelline fluid is synthesized by the albumen gland of female snails (also known as albumen gland-capsule gland complex or uterine gland), an accessory gland from the reproductive tract. Fertilized oocytes enter the albumen gland and, on their way out, are coated with the perivitelline fluid. The amount of perivitelline fluid per egg vary considerably among species. However, the amount of perivitelline fluid per egg is constant wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antioxidant
Antioxidants are compounds that inhibit oxidation, a chemical reaction that can produce free radicals. This can lead to polymerization and other chain reactions. They are frequently added to industrial products, such as fuels and lubricants, to prevent oxidation, and to foods to prevent spoilage, in particular the rancidification of oils and fats. In cells, antioxidants such as glutathione, mycothiol or bacillithiol, and enzyme systems like superoxide dismutase, can prevent damage from oxidative stress. The only dietary antioxidants are vitamins A, C, and E, but the term ''antioxidant'' has also been applied to numerous other dietary compounds that only have antioxidant properties in vitro, with little evidence for antioxidant properties in vivo. Dietary supplements marketed as antioxidants have not been shown to maintain health or prevent disease in humans. History As part of their adaptation from marine life, terrestrial plants began producing non-marine antioxi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photoprotection
Photoprotection is the biochemical process that helps organisms cope with molecular damage caused by sunlight. Plants and other oxygenic phototrophs have developed a suite of photoprotective mechanisms to prevent photoinhibition and oxidative stress caused by excess or fluctuating light conditions. Humans and other animals have also developed photoprotective mechanisms to avoid UV photodamage to the skin, prevent DNA damage, and minimize the downstream effects of oxidative stress. In photosynthetic organisms In organisms that perform oxygenic photosynthesis, excess light may lead to photoinhibition, or photoinactivation of the reaction centers, a process that does not necessarily involve chemical damage. When photosynthetic antenna pigments such as chlorophyll are excited by light absorption, unproductive reactions may occur by charge transfer to molecules with unpaired electrons. Because oxygenic phototrophs generate O2 as a byproduct from the photocatalyzed splitting of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
