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protein /pro·tein/ (pro´tēn) any of a group of complex organic compounds containing carbon, hydrogen, oxygen, nitrogen, and sulfur. Proteins, the principal constituents of the protoplasm of all cells, are of high molecular weight and consist of α-amino acids joined by peptide linkages. Twenty different amino acids are commonly found in proteins, each protein having a unique, genetically defined amino acid sequence that determines its specific shape and function. Their roles include enzymatic catalysis, transport and storage, coordinated motion, nerve impulse generation and transmission, control of growth and differentiation, immunity, and mechanical suppport.
AA protein see under amyloid. acute phase protein any of the non-antibody proteins found in increased amounts in serum during the acute phase response, including C-reactive protein and fibrinogen. AL protein see under amyloid. amyloid A protein AA amyloid. amyloid light chain protein AL amyloid. amyloid precursor protein (APP) a large transmembrane glycoprotein expressed on the cell surface and of uncertain function; endocytosis and cleavage can produce abnormal 40 to 43 amino acid peptides which aggregate to form A, associated with Alzheimer's disease. Bence Jones protein a low-molecular-weight, heat-sensitive urinary protein found in multiple myeloma, which coagulates when heated to 45°–55°C and redissolves partially or wholly on boiling. binding protein 1. any protein able to specifically and reversibly bind other substances, such as ions, sugars, nucleic acids, or amino acids; they are believed to function in transport. 2. transport p. protein C a vitamin K–dependent plasma protein that, when activated by thrombin, inhibits the clotting cascade by enzymatic cleavage of factors V and VIII and also enhances fibrinolysis. Deficiency results in recurrent venous thrombosis. C4 binding protein a complement system regulatory protein that inhibits activation of the classical pathway. complete protein one containing the essential amino acids in the proportion required in the human diet. compound protein , conjugated protein any of those in which the protein is combined with nonprotein molecules or prosthetic groups other than as a salt; e.g., nucleoproteins, glycoproteins, lipoproteins, and metalloproteins. C-reactive protein a globulin that forms a precipitate with the C-polysaccharide of the pneumonococcus; the most predominant of the acute phase proteins. cystic fibrosis transmembrane regulator protein a transmembrane protein produced by the cystic fibrosis gene, primarily functioning as a chloride channel. Numerous mutated forms of the gene have been associated with clinical cystic fibrosis. fibrillar protein any of the generally insoluble proteins that comprise the principal structural proteins of the body, e.g., collagens, elastins, keratin, actin, and myosin. G protein any of a family of proteins of the intracellular portion of the plasma membrane that bind activated receptor complexes and, through conformational changes and cyclic binding and hydrolysis of GTP, effect alterations in channel gating and so couple cell surface receptors to intracellular responses. glial fibrillary acidic protein (GFAP) the protein forming the glial filaments of the astrocytes and used as an immunohistochemical marker of these cells. globular protein any of the water-soluble proteins yielding only α-amino acids on hydrolysis, including most of the proteins of the body, e.g., albumins and globulins. guanyl-nucleotide-binding protein G p. heat shock protein any of a group of proteins first identified as synthesized in response to hyperthermia, hypoxia, or other stresses and believed to enable cells to recover from these stresses. Many have been found to be molecular chaperones and are synthesized abundantly regardless of stress. HIV proteins proteins specific to the human immunodeficiency virus; presence of certain specific HIV proteins together with certain HIV glycoproteins constitutes a serological diagnosis of HIV infection. incomplete protein one having a ratio of essential amino acids different from that of the average body protein. membrane cofactor protein (MCP) an inhibitor of complement activation found in most blood cells, endothelial and epithelial cells, and fibroblasts. myeloma protein any of the abnormal immunoglobulins or fragments, such as Bence-Jones proteins, secreted by myeloma cells. partial protein incomplete p. plasma proteins all the proteins present in the blood plasma, including the immunoglobulins. prion protein (PrP) a protein of uncertain function, in humans coded for by a gene on the short arm of chromosome 20. The protease-resistant core is the functional, and perhaps only, component of prions; several abnormal forms have been identified and are responsible for prion disease. protein S a vitamin K–dependent plasma protein that inhibits blood clotting by serving as a cofactor for activated protein C. S protein see vitronectin. SAA protein serum amyloid A p. serum proteins proteins in the blood serum, including immunoglobulins, albumin, complement, coagulation factors, and enzymes. serum amyloid A protein SAA p.; a high-molecular-weight protein synthesized in the liver; it is an acute phase protein and circulates in association with HDL lipoprotein. It is the precursor to AA amyloid and accumulates in inflammation. sphingolipid activator protein (SAP) any of a group of non-enzymatic lysosomal proteins that stimulate the actions of specific lysosomal hydrolases by binding and solubilizing their sphingolipid substrates. transport protein a protein that binds to a substance and provides a transport system for it, either in the plasma or across a plasma membrane.
Protein A substance produced by a gene that is involved in creating the traits of the human body, such as hair and eye color, or is involved in controlling the basic functions of the human body, such as control of the cell cycle. Mentioned in: Acoustic Neuroma, Gene Therapy, Phenylketonuria, Retinoblastoma, Von Willebrand Disease
protein [prō′tē·in, prō′tēn] Etymology: Gk, proteios, first rank any of a large group of naturally occurring complex organic nitrogenous compounds. Each is composed of large combinations of amino acids (usually 50 or more) containing the elements carbon, hydrogen, nitrogen, oxygen, and occasionally sulfur, phosphorus, iron, iodine, or other essential constituents of living cells. Twenty-two amino acids have been identified as vital for proper growth, development, and maintenance of health. The body can synthesize 13 of these, the nonessential amino acids, whereas the remaining 9 must be obtained from dietary sources and are termed essential. Protein is the major source of building material for muscles, blood, skin, hair, nails, and the internal organs. It is necessary for the formation of many hormones, enzymes, and antibodies and may act as a source of energy. Rich dietary sources are meat, poultry, fish, eggs, milk, and cheese, which are classified as complete proteins because they contain the nine essential amino acids. Nuts and legumes, including navy beans, chickpeas, soybeans, and split peas, are also good sources but are incomplete proteins because they do not contain all the essential amino acids in adequate amounts. Protein deficiency causes abnormal growth and tissue development in children, leading to kwashiorkor, whereas in adults it results in lack of vigor and stamina, weakness, mental depression, poor resistance to infection, impaired healing of wounds, and slow recovery from disease. Excessive intake of protein may in some conditions result in fluid imbalance. protein/creatinine ratio, the ratio of protein to creatinine in the urine, calculated as a measure of proteinuria. protein (prō´tēn), n a group of complex organic nitrogenous compounds; the principal constituent of cell protoplasm. Polymers of amino acids that are joined by peptide or amide bonds. protein, anabolic, n See steroid, C-19 cortico. protein, Bence Jones, n.pr a special protein found in the blood and urine of patients with multiple myeloma and occasionally other diseases involving bone marrow, such as sarcoma and leukemia. protein, bone morphogenetic (BMP) n one of several genetically produced proteins that promotes the formation of bone and cartilage. protein, C-reactive, n a mucoprotein whose presence in serum is always abnormal. It may be present in a variety of inflammatory or necrotic disease processes. It is almost always present in the serum in acute rheumatic fever. protein chemical score (CS), n the result of a comparison between the amount of essential amino acid in a dietary protein and the amount in a reference protein. protein, complementary, n a protein that is incomplete on its own but may become complete when combined with other proteins to provide all the amino acids necessary for normal metabolism. protein, complete, n a protein that contains ample amounts of all the amino acids necessary for normal metabolism; animal proteins. protein, deficiency, n See deficiency, protein. protein efficiency ratio (PER), n a calculation designed to assess an individual protein's ability to sustain growth. protein incomplete, n a protein that is missing one or more of the amino acids necessary for normal metabolism; vegetable protein. protein kinase, n a protein that catalyzes the transfer of a phosphate group from adenosine triphosphate to produce a phosphoprotein. protein, plasma, n blood serum contains 6.5 to 8 grams percent of a complex mixture of proteins, including albumin, globulin, and fibrinogen. protein, reference, n a protein, usually egg, against which other proteins may be measured to evaluate their capability for supporting synthesis. protein, spare, n one of several roles a carbohydrate food may play in a well-balanced diet. Many foods that are technically classified as carbohydrates, including some whole grains and beans, contain relatively significant amounts of protein that may, therefore, be referred to as spare. protein specificity, n the arrangement of protein molecules in numerous spatial configurations to suit the special needs of the physical and chemical activities of the cell. The wide degree of variability of protein structures permits a high degree of specificity of tissue within one body. This characteristic of protein specificity is of great significance in blood transfusions, tissue grafts, and many allergic manifestations. protein, thromboplastic,
n See factor III. protein any large organic compound made from one or more polypeptides, which are chains of amino acids joined in a genetically determined order by peptide linkages between the carboxyl group of one amino acid and the amino group of the next. They contain carbon, hydrogen, oxygen and nitrogen and usually sulfur, occasionally phosphorus. Proteins form a large and essential part of the body mass, comprising especially cell membranes, connective tissue, muscles, enzymes, hormones, blood proteins. To maintain this mass the diet must contain a high proportion of protein, especially in growing animals and those recovering from debilitating diseases. protein A a surface protein of Staphylococus aureus which binds to the Fc region of some IgG molecules. Fluorochrome-labeled protein A is used in an indirect immunofluorescence test for detecting bound immunoglobulins. authentic protein a recombinant protein with all its naturally occurring properties. available protein the portion of dietary protein that can be used by the animal. protein binding a property of many drugs which limits their distribution and availability in the blood, as well as affecting elimination from the body. protein bumps see bumps. protein C a circulating vitamin K-dependent protein with anticoagulant effects. Promotes fibrinolysis. protein-calories calories derived from proteins in the diet. protein calorie malnutrition inadequate protein in the diet leads to impaired cell-mediated immunity, delayed wound healing and loss of lean body mass. protein-calorie ratio the number of calories provided from protein sources, compared with the total caloric intake; an indication of the level of protein intake. carrier protein one which, when coupled to a hapten, renders it capable of eliciting an immune response. complete protein one containing the essential amino acids in the proportion required in the diet. protein concentrates feeds containing a high concentration of protein, e.g. legume grains and forages, meat meal, fish meal, oil cakes, milling residues including bran, shorts, middlings, brewer's grains. conjugated p's those in which the protein molecule is united with nonprotein molecules or prosthetic groups, e.g. glycoproteins, lipoproteins and metalloproteins. protein-creatinine ratio in urine is valuable in correcting for variation in urine contents due to variable dilutions. crude protein the total nitrogen content of a feed multiplied by 6.25. Includes several obvious errors but is still a close approximation of the protein content. dietary protein is usually the most expensive part of the diet, except for animals at pasture, and the constituent most likely to be deficient. An excess of protein in the diet in ruminants can cause a sharp rise in alkalinity, due to the release of ammonia, of the ruminal contents causing ruminal atony and indigestion. digestible protein the crude protein ingested less the protein excreted in the feces. The estimation requires a digestibility trial involving animals. protein equivalent said of a feed. The total nitrogen content expressed as protein if it were all in that form. That is the percentage nitrogen in the feed multiplied by the average percentage of nitrogen in plant protein (6.25%). protein excretion t one that uses 51Cr-labeled protein which measures protein excretion in the feces in cases of protein-losing enteropathy. protein-fibrinogen ratio see plasma protein:fibrinogen ratio. fibrous p's characterized by shape, structure and low water solubility; they have a structural role. Examples are collagen, keratin and tropomyosin. fusion protein in recombinant DNA technology when a foreign gene is inserted into a plasmid vector to interrupt a gene, such as lacZ, the mRNA transcript of the recombinant plasmid contains the lacZ Shine-Dalgarno sequence and codons for the 3′ end of the lacZ gene protein followed by the codons of the foreign gene; the protein expressed is a fusion protein containing a few N-terminal lacZ amino acids and the contiguous foreign protein. protein hydrolysates pharmaceutical preparations used in the treatment of severe, acute protein loss. Available for use orally or parenterally. They are partly digested proteins and contain a mixture of polypeptides, amino acids and other breakdown products. protein microarray an ordered set of small samples of proteins immobilized on a microscope slide or other solid surface that is used to determine protein-protein interactions. myeloma protein see multiple myeloma. protein nutritional deficiency causes lack of muscle development, and slow growth rate and maturation. In adults there is a low milk production and poor weight gain. In severe states tissue and blood levels fall, hypoproteinemic edema may occur, and a degree of immunosuppression could be expected. partial protein one having a ratio of essential amino acids different from that of the average body protein. peripheral protein any protein located in the membrane but not essential to the reconstitution of that protein. plasma p's all the proteins present in the blood plasma, including the immunoglobulins. See plasma protein. polyhedrin matrix protein a protein that comprises the major component of occlusion bodies produced by nuclear polyhedrosis virus and cytoplasmic polyhedrosis virus; the strong polyhedrin promoter is utilized in the expression of recombinant proteins in baculovirus expression systems. rec A protein an enzyme that binds to DNA and plays an important role in genetic recombination. protein S a circulating vitamin K-dependent protein with anticoagulant effects. serum protein proteins in the blood serum, including immunoglobulins, albumin, complement, coagulation factors and enzymes. protein shock anaphylaxis occurring after the intravenous injection of protein. protein-sparing in times of energy deficiency the animal body may raid protein stores for glucogenic amino acids, thus depleting body stores of proteins. Substances such as acetic acid which can fill the energy deficiency and avoid the protein loss are known as protein-sparing. protein supplements feeds which contain more than 20% protein. urine protein see proteinuria. viral protein
proteins encoded by the viral genome. protein Complex organic molecule composed of various combinations of any of twenty α-amino acids linked in a genetically controlled linear sequence into one or more peptide chains. Proteins are present in every living cell and form an essential constituent of cells. They are essential in many functions, such as growth and repair of tissue, transport of molecules throughout the body (e.g. haemoglobin to carry oxygen), as enzymes to catalyse biochemical reactions, immunological responses, muscle contraction (with actin and myosin), signalling (e.g. insulin which transmits a signal from a cell where it is synthesized to other cells in other tissues), or as antibodies by binding to target receptors. Many of the twenty amino acids are produced by the body. However, nine of these have to be obtained in food.
protein Biochemistry A large molecule consisting of a long chain or sequence of amino acids with a general formula of H2N–CHR–COOH–aka alpha amino acids, joined in a peptide likage; after water, proteins are the
major cell constituent, and are critical for all biological structures–eg, organelles, mitochondria, enzymes and functions–eg, growth, development, immune function, motility Types Hormones, enzymes, antibodies Patient discussion about protein. Q. Well I’m a vegetarian and I might get anemia. How do I get Iron and protein without meat? My mom my take giant vitamin pills and eat nasty protein bars. It's not as bad killing animals though... Is their any way I can stay healthy? Also being a vegetarian has made me extremely under weight and I am probably going to get anemia if i don't get all my vitamins. HELP! A. You are, at least partially, what you eat, so it's important to take care of your diet. Being underweight, especially during adolescence, may pose substantial risk to the health. If your diet caused you to be underweight I would consider consulting a professional (e.g doctor, dietitian). Iron from vegetables is not as good as iron from meat. Foods rich in iron include whole or enriched breads or grains, iron-fortified cereals, legumes, green leafy vegetables, dried fruits, soy products, blackstrap molasses, bulgur, and wheat germ. Vitamin C helps the body to absorb the iron from the food better. You may read more here: http://www.nlm.nih.gov/medlineplus/vegetariandiet.html Q. How much protein should an 18 month old male toddler have daily? A. According to The Food and Nutrition Board and The Institute of Medicine, the Dietary Reference Intakes (DRI) for a toddler aged 1 to 3 include: 1.Protein: A minimum of 16 grams a day. 16 ounces of milk plus one ounce of meat is ample protein for a toddler. 2.Fat: At least 30% of a toddler's calories should come from fat. Too little can result in "failure to thrive" where children do not get enough food to supply their energy and growth needs. 3.Calories: approximately 1000 to 1300calories/day. Calorie distribution is apt to look like this: 13 g Protein = 52 calories 44 g Fat = 396 calories 175 g Carbohydrate = 702 calories Total = 1150 calories For the complete list you can go to: http://www.earthsbest.com/toddler_nutrition/articles/feeding_toddlers.php Q. What foods or liquids, juices, proteins, fruits, are good for Male Prostate or Urinary Frequency? I am 53 YO Male with exessive urinary frequency. Is there a fruit, food, drink, pill, mojo, that would help me with this problem? I am talking about urinating 3 to 4 times every night, and or while watching TV, every hour or so. No pain, yet, an occacional after drip that is very anoying. Perhaps I have a prostate problem and should consuld with my Urologist. Yet, before I go there, does anyone know of something I can eat or drink to fix or aleviate this problem? A. I don't know about any food that specifically targets this problem, although some steps you may take include avoiding fluids prior to bedtime or before going out, reducing consumption of mild diuretics (substances that make you produce urine) such as caffeine and alcohol, and double voiding to empty the bladder more completely. Read more or ask a question about proteinYou may read more here (www.mayoclinic.com/health/enlarged-prostate-bph/BP99999 ), and as you wrote, consulting a doctor may be wise. Want to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit the webmaster's page for free fun content. |
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