Oxidative refolding of recombinant prochymosin. (1/91)The disulphide-coupled refolding of recombinant prochymosin from Escherichia coli inclusion bodies was investigated. Prochymosin solubilized from inclusion bodies is endowed with free thiol groups and disulphide bonds. This partially reduced form undergoes renaturation more efficiently than the fully reduced form, suggesting that some native structural elements existing in inclusion bodies and remaining after denaturation function as nuclei to initiate correct refolding. This assumption is supported by the finding that in the solubilized prochymosin molecule the cysteine residues located in the N-terminal domain of the protein are not incorrectly paired with the other cysteines in the C-terminal domain. Addition of GSH/GSSG into the refolding system facilitates disulphide rearrangement and thus enhances renaturation, especially for the fully reduced prochymosin. Based on the results described in this and previous papers [Tang, Zhang and Yang (1994) Biochem. J. 301, 17-20], a model to depict the refolding process of prochymosin is proposed. Briefly, the refolding process of prochymosin consists of two stages: the formation and rearrangement of disulphide bonds occurs at the first stage in a pH11 buffer, whereas the formation and adjustment of tertiary structure leading to the native conformation takes place at the second stage at pH8. The pH11 conditions help polypeptides to refold in such a way as to favour the formation of native disulphide bonds. Disulphide rearrangement, the rate-limiting step during refolding, can be achieved by thiol/disulphide exchange initiated by free thiol groups present in the prochymosin polypeptide, GSH/GSSG or protein disulphide isomerase. (+info)
New world monkey pepsinogens A and C, and prochymosins. Purification, characterization of enzymatic properties, cDNA cloning, and molecular evolution. (2/91)Pepsinogens A and C, and prochymosin were purified from four species of adult New World monkeys, namely, common marmoset (Callithrix jacchus), cotton-top tamarin (Saguinus oedipus), squirrel monkey (Saimiri sciureus), and capuchin monkey (Cebus apella). The occurrence of prochymosin was quite unique since this zymogen is known to be neonate-specific and, in primates, it has been thought that the prochymosin gene is not functional. No multiple form has been detected for any type of pepsinogen except that two pepsinogen-A isozymogens were identified in capuchin monkey. Pepsins A and C, and chymosin hydrolyzed hemoglobin optimally at pH 2-2.5 with maximal activities of about 20, 30, and 15 units/mg protein. Pepsins A were inhibited in the presence of an equimolar amount of pepstatin, and chymosins and pepsins C needed 5- and 100-fold molar excesses of pepstatin for complete inhibition, respectively. Hydrolysis of insulin B chain occurred first at the Leu15-Tyr16 bond in the case of pepsins A and chymosins, and at either the Leu15-Tyr16 or Tyr16-Leu17 bond in the case of pepsins C. The presence of different types of pepsins might be advantageous to New World monkeys for the efficient digestion of a variety of foods. Molecular cloning of cDNAs for three types of pepsinogens from common marmoset was achieved. A phylogenetic tree of pepsinogens based on the nucleotide sequence showed that common marmoset diverged from the ancestral primate about 40 million years ago. (+info)
A basic residue at position 36p of the propeptide is not essential for the correct folding and subsequent autocatalytic activation of prochymosin. (3/91)Position 36p in the propeptides of gastric aspartic proteinases is generally occupied by lysine or arginine. This has led to the conclusion that a basic residue at this position, which interacts with the active-site aspartates, is essential for folding and activation of the zymogen. Lamb prochymosin has been shown by cDNA cloning to possess glutamic acid at 36p. To investigate the effect of this natural mutation which appears to contradict the proposed role of this residue, calf and lamb prochymosins and their two reciprocal mutants, K36pE and E36pK, respectively, were expressed in Escherichia coli, refolded in vitro, and autoactivated at pH 2 and 4.7. All four zymogens could be activated to active chymosin and, at both pH values, the two proteins with Glu36p showed higher activation rates than the two Lys36p forms. Glu36p was also demonstrated in natural prochymosin isolated from the fourth stomach of lamb, as well as being encoded in the genomes of sheep, goat and mouflon, which belong to the subfamily Caprinae. A conserved basic residue at position 36p of prochymosin is thus not obligatory for its folding or autocatalytic activation. The apparently contradictory results for porcine pepsinogen A [Richter, C., Tanaka, T., Koseki, T. & Yada, R.Y. (1999) Eur. J. Biochem. 261, 746-752] can be reconciled with those for prochymosin. Lys/Arg36p is involved in stabilizing the propeptide-enzyme interaction, along with residues nearer the N-terminus of the propeptide, the sequence of which varies between species. The relative contribution of residue 36p to stability differs between pepsinogen and prochymosin, being larger in the former. (+info)
Cathepsin D isozymes from porcine spleens. Large scale purification and polypeptide chain arrangements. (4/91)Six cathepsin D isozymes have been purified from porcine spleen using a large scale purification procedure. Five isozymes, I to V, have an identical molecular weight of 50,000 and are similar in specific activity. Isozymes I to IV contained two polypeptide chains each. The light and heavy chains have Mr = 15,000 and 35,000, respectively. Isozyme V is a single polypeptide. The molecular weight of the sixth isozyme is about 100,000 and it has only 5% of the specific activity of the other isozymes. On Ouchterlony immunodiffusion, an antiserum formed precipitin lines against the urea-denatured isozyme with Mr = 100,000. This immunoreactivity showed immunoidentity with those formed against other isozymes. The NH2-terminal sequence of light chains was identical for the isozymes. This sequence is homologous to the NH2-terminal sequence of other acid proteases, especially near the region of the active center aspartate-32. The NH2-terminal sequence of the single chain, isozyme V, Is apparently the same as the light chain sequence. The NH2-terminal sequence analysis of the heavy chain from isozyme I produced two sets of related sequences, suggesting the prescene of structural microheterogeneity. The carbohydrate analysis of the isozymes, the light chain, and the heavy chain revealed the presence of possibly four attachment sites, with one in the light chain and three in the heavy chain. Each carbohydrate unit contains 2 residues of mannose and 1 residue of glucosamine. The results suggest that the high molecular weight cathepsin D (Mr = 100,000) is the probable precursor of the single chain (Mr = 50,000), which in turn produces the two-chain isozymes. These are likely in vivo processes. (+info)
Precise and efficient cleavage of recombinant fusion proteins using mammalian aspartic proteases. (5/91)Expression of recombinant proteins as translational fusions is commonly employed to enhance stability, increase solubility and facilitate purification of the desired protein. In general, such fusion proteins must be cleaved to release the mature protein in its native form. The usefulness of the procedure depends on the efficiency and precision of cleavage and its cost per unit activity. We report here the development of a general procedure for precise and highly efficient cleavage of recombinant fusion proteins using the protease chymosin. DNA encoding a modified pro-peptide from bovine chymosin was fused upstream of hirudin, carp growth hormone, thioredoxin and cystatin coding sequences and expressed in a bacterial Escherichia coli host. Each of the resulting fusion proteins was efficiently cleaved at the junction between the pro-peptide and the desired protein by the addition of chymosin, as determined by activity, N-terminal sequencing and mass spectrometry of the recovered protein. The system was tested further by cleavage of two fusion proteins, cystatin and thioredoxin, sequestered on oilbody particles obtained from transgenic Arabidopsis seeds. Even when the fusion protein was sequestered and immobilized on oilbodies, precise and efficient cleavage was obtained. The precision, efficiency and low cost of this procedure suggest that it could be used in larger scale manufacturing of recombinant proteins which benefit from expression as fusions in their host organism. (+info)
Improvement of foreign-protein production in Aspergillus niger var. awamori by constitutive induction of the unfolded-protein response. (6/91)Unfolded-protein response (UPR) denotes the upregulation of endoplasmic reticulum (ER)-resident chaperone and foldase genes and numerous other genes involved in secretory functions during the accumulation of unfolded proteins into the ER. Overexpression of individual foldases and chaperones has been used in attempts to improve protein production in different production systems. We describe here a novel strategy to improve foreign-protein production. We show that the constitutive induction of the UPR pathway in Aspergillus niger var. awamori can be achieved by expressing the activated form of the transcription factor hacA. This induction enhances the production of Trametes versicolor laccase by up to sevenfold and of bovine preprochymosin by up to 2.8-fold in this biotechnically important fungus. The regulatory range of UPR was studied by analyzing the mRNA levels of novel A. niger var. awamori genes involved in different secretory functions. This revealed both similarities and differences to corresponding studies in Saccharomyces cerevisiae. (+info)
Calf chymosin as a catalyst of peptide synthesis. (7/91)Calf chymosin was shown to catalyse peptide synthesis optimally over the range pH 4-5, giving satisfactory yields of methyl esters or p-nitroanilides of benzyloxycarbonyl tetra- to hexa-peptides, provided that hydrophobic amino-acid residues form the new peptide bonds. The effectiveness of the enzyme depends also on the nature of adjacent amino-acid residues. As an aspartate-proteinase with a characteristic specificity pattern chymosin would be useful for the synthesis of middle-length peptides. (+info)
Characterization and study of a kappa-casein-like chymosin-sensitive linkage. (8/91)The present report is dealing with the identification, in various unrelated proteins, of protein fragments sharing local sequence and structure similarities with the chymosin-sensitive linkage surrounding the Phe-Met/Ile bond of kappa-caseins. In all these proteins, this linkage is observed within an exposed beta-strand-like structure, as also predicted for kappa-caseins. The structure of one of these fragments, included in glutamine synthetase, particularly superimposes well with the conformation observed for a chymosin inhibitor (CP-113972) within the complex it forms with chymosin and can be similarly accommodated by specificity pockets within the enzyme substrate binding cleft. The effect of the enzyme activity of chymosin was thus tested on glutamine synthetase. Chymosin cut the latter at the Phe-Met linkage, suggesting that this system may locally resemble the kappa-casein/chymosin complex. (+info)
Chymosin is an enzyme that is produced by the cells of the fourth stomach of ruminant animals, such as cows and sheep. It is also known as rennin, and is used in the production of cheese. In the medical field, chymosin is used to help digest proteins in the stomach and small intestine. It is also used to treat certain digestive disorders, such as lactose intolerance and acid reflux. Chymosin is available as a medication and is usually taken by mouth.
Autolysis is a process in which cells or tissues break down and degrade themselves. In the medical field, autolysis can occur as a result of injury, infection, or other factors that damage cells or tissues. Autolysis can be a normal process in the body, such as during the breakdown of dead or damaged cells in the immune response. However, excessive autolysis can lead to tissue damage and inflammation, which can contribute to the development of various medical conditions. In some cases, autolysis can be accelerated by the presence of enzymes or other substances that break down cell components. For example, during the decomposition of a dead body, the enzymes produced by bacteria and fungi can accelerate the process of autolysis, leading to the characteristic smell and appearance of a decaying body. In the medical field, autolysis can be a concern in situations where cells or tissues are damaged or injured, such as in traumatic injuries or surgical procedures. In these cases, efforts may be made to prevent or slow down the process of autolysis to minimize tissue damage and promote healing.
In the medical field, the term "camels" is not commonly used. However, there are a few medical terms that contain the word "camel" in their name, such as: 1. Camel's Hump: This is a medical condition characterized by the accumulation of fat in the back of the neck, which gives the appearance of a hump. It is usually associated with obesity and diabetes. 2. Camel's Toe: This is a medical condition characterized by the protrusion of the skin between the toes, which gives the appearance of a camel's toe. It is usually caused by wearing tight-fitting shoes or genetic factors. 3. Camel's Hump Syndrome: This is a rare genetic disorder characterized by the accumulation of fat in the back of the neck, as well as other symptoms such as short stature, intellectual disability, and skeletal abnormalities. It's important to note that these medical terms are not related to the animal kingdom, but rather to specific medical conditions or syndromes.
Caseins are a group of proteins found in milk and other dairy products. They are the major protein component of milk and are responsible for its thick, creamy texture. There are four main types of caseins: alpha-casein, beta-casein, kappa-casein, and omega-casein. These proteins are important for the nutritional value of milk and are also used in the production of cheese and other dairy products. In the medical field, caseins have been studied for their potential health benefits, including their ability to promote bone health and reduce the risk of certain diseases. However, more research is needed to fully understand the effects of caseins on human health.
In the medical field, "cheese" is not a commonly used term. However, there are some medical conditions that may be referred to as "cheese-like" or "cheesy" in appearance or texture. One example is a condition called "cheesy pustules," which is a type of skin lesion that can occur in certain skin infections, such as impetigo or folliculitis. These lesions are characterized by a yellowish-white, pus-filled bump that may be surrounded by redness and swelling. Another example is "cheesy brain," which is a term used to describe a type of brain injury called diffuse axonal injury. This type of injury occurs when the brain is subjected to a sudden, violent force, such as a car accident or a sports injury. The injury can cause damage to the brain's axons, which are the long, slender fibers that transmit signals between nerve cells. The damaged axons can become tangled and twisted, creating a "cheesy" appearance on an MRI scan of the brain. Overall, while "cheese" is not a commonly used term in the medical field, there are some medical conditions that may be referred to as "cheesy" in appearance or texture.
Aspergillus oryzae is a species of fungus that is commonly found in soil, decaying plant matter, and on grains such as rice and wheat. It is a filamentous fungus that produces spores that can be inhaled and cause respiratory problems in humans and animals. In the medical field, A. oryzae is primarily known for its use in the production of enzymes and other compounds that have various industrial and medical applications. For example, it is used to produce amylases, proteases, and lipases, which are enzymes that are used in the food and beverage industry to break down complex carbohydrates, proteins, and fats, respectively. A. oryzae is also used in the production of koji, a traditional Japanese food ingredient made by fermenting rice or other grains with the fungus. Koji is used in the production of various traditional Japanese foods, including miso, soy sauce, and sake. In addition to its industrial uses, A. oryzae has been studied for its potential medicinal properties. Some studies have suggested that it may have anti-inflammatory, anti-cancer, and anti-bacterial effects, although more research is needed to confirm these findings.
Enzyme precursors are the inactive forms of enzymes that are synthesized in the body and need to be activated before they can perform their specific functions. Enzymes are proteins that catalyze chemical reactions in the body, and they play a crucial role in various physiological processes such as digestion, metabolism, and energy production. Enzyme precursors are usually synthesized in the liver and other organs and are transported to the cells where they are needed. Once inside the cells, they are activated by a process called proteolysis, which involves the cleavage of specific amino acid bonds in the enzyme precursor molecule. Enzyme precursors are important for maintaining proper enzyme function and activity in the body. Deficiencies in enzyme precursors can lead to enzyme deficiencies, which can cause a range of health problems. For example, a deficiency in the enzyme precursor for the enzyme lactase can lead to lactose intolerance, a condition in which the body is unable to digest lactose, a sugar found in milk and other dairy products.
HLA-B7 is a human leukocyte antigen (HLA) molecule that plays a crucial role in the immune system. It is a type of protein found on the surface of most cells in the body, and it helps the immune system recognize and respond to foreign substances, such as viruses and bacteria. HLA-B7 is a member of the HLA-B group of antigens, which are a subset of the HLA class I antigens. HLA-B7 is encoded by the HLA-B*07 gene, which is located on chromosome 6. There are several different variants of the HLA-B7 antigen, each with slightly different amino acid sequences and properties. The HLA-B7 antigen is expressed on the surface of cells that are infected with viruses or bacteria, and it is recognized by T cells, a type of white blood cell that plays a key role in the immune response. When a T cell recognizes an HLA-B7 molecule on the surface of an infected cell, it becomes activated and releases chemicals that can kill the infected cell or help other immune cells respond to the infection. In addition to its role in the immune response, HLA-B7 has also been implicated in the development of certain autoimmune diseases, such as rheumatoid arthritis and multiple sclerosis. In these conditions, the immune system mistakenly attacks healthy cells that express the HLA-B7 antigen, leading to inflammation and tissue damage.
Foodborne diseases, also known as foodborne illnesses or food poisoning, are caused by consuming contaminated food or beverages. These diseases can be caused by a variety of microorganisms, such as bacteria, viruses, parasites, and fungi, as well as chemical substances and toxins. Foodborne diseases can cause a range of symptoms, including nausea, vomiting, diarrhea, abdominal pain, fever, and headache. In severe cases, they can lead to hospitalization, disability, and even death. Preventing foodborne diseases involves proper food handling, storage, and preparation techniques, as well as ensuring that food is cooked to the appropriate temperature and consumed before it spoils. It is also important to practice good hygiene, such as washing hands and surfaces frequently, and avoiding cross-contamination between raw and cooked foods. In the medical field, foodborne diseases are typically diagnosed through a combination of symptoms, medical history, and laboratory tests. Treatment may involve supportive care, such as rehydration therapy, as well as antibiotics or antiviral medications if the disease is caused by a bacterial or viral infection.
Bacteria are single-celled microorganisms that are found in almost every environment on Earth, including soil, water, and the human body. In the medical field, bacteria are often studied and classified based on their characteristics, such as their shape, size, and genetic makeup. Bacteria can be either beneficial or harmful to humans. Some bacteria are essential for human health, such as the bacteria that live in the gut and help digest food. However, other bacteria can cause infections and diseases, such as strep throat, pneumonia, and meningitis. In the medical field, bacteria are often identified and treated using a variety of methods, including culturing and identifying bacteria using specialized laboratory techniques, administering antibiotics to kill harmful bacteria, and using vaccines to prevent bacterial infections.
Perfect Day (company)
Genetically modified food
History of genetic engineering
Gastric chief cell
Manufacture of cheddar cheese
Ken R. Harewood
Genetically modified bacteria
Food and drink prohibitions
Yeast expression platform
Genetically modified organism
List of MeSH codes (D08)
Protein engineering of loops in chymosin and expression in Trichoderma reesei<...
Chymosin CAS 9001-98-3 Rennet por 20000u / g Chymosin por 20000u / g Chymosin por - enzymes.bio
Cheesemaking Supplies Wholesale | Best Cheese Ingredients & Equipment- Now Additional 15% Off! | The CheeseMaker
About rennet - Dairy Science and Food Technology Forum
"Effects of Filtration Temperature and Heat Treatment on Composition an" by John W. Montella
NIOSHTIC-2 Search Results - Full View
Food and Drug Regulations
US Patent for Method for cleavage of fusion proteins Patent (Patent # 7,531,325 issued May 12, 2009) - Justia Patents Search
Papain, afikun enzymu, potasiomu sorbate, awọn olupese Kannada
Joint Support - torsineen
On the trail of milk & cheese
Homology modeling and functional annotation of bubaline pregnancy associated glycoprotein 2 | Journal of Animal Science and...
Which one of the following is a fat-soluble vitamin and its related deficiency disease? | Digestion and Absorption
Maxiren - Carbon Group
NATURAL LIQUID PASTE LAMB - 75PS140 - Walcoren
Mechanically activated hydrolysis of plant-derived proteins in food industry
Lene Jespersen - Research outputs - Staff of the Department of Food Science
gastric juice (HyperDic hyper-dictionary)
Brandy Archives - Vintage American Cocktails
Newest 'digestive-system' Questions - Biology Stack Exchange
do camels throw up their stomachs
Pesquisa | Prevenção e Controle de Câncer
ISO/TC 34/SC 5 - Milk and milk products
August | 2017 | Gp120 Inhibitor
vegetarian parmesan cheese Archives - Healthy Vegan Indian Food for Lunch, Take-out & Delivery | Bombay Sandwich Co. | Flatiron
- Safety evaluation of the food enzyme rennet containing chymosin and pepsin A from the abomasum of calves and cows. (bvsalud.org)
- The enzyme chymosin is then added to the liquid, which causes the milk to curdle. (gymbeam.com)
- The food enzyme containing chymosin (EC 126.96.36.199) and pepsin A (EC 188.8.131.52) is prepared from the abomasum of calves and cows ( Bos taurus ) by Chr. (bvsalud.org)
- A search for the similarity of the amino acid sequences of the two proteins ( chymosin and pepsin A ) to those of known allergens was made and one match with pig pepsin , a respiratory allergen , was found. (bvsalud.org)
- Although nobody marinates their meat with cheese, cheeses contain proteases also, such as chymosin, trypsin and pepsin. (acs.org)
- The sole suited mineral deposits which they can use during aggressive connected with balm parmesan dairy product to be removed with Canada happen to be chymosin A you need to Ymca, pepsin to locate a rennet. (go.ke)
- The matched nutrients that can be used found at conventional associated with salve cheese to be removed on Canada usually are chymosin Your to locate a Y simply, pepsin and start rennet. (starlanguage.vn)
- Recognition of recombinant chymosin as safe enzyme, finds the use of first recombinant product in cheese making in 1990. (lexorbis.com)
- Chymosin, an aspartic acid protease, is initiating milk coagulation in cheese manufacturing by cleaving off the glycomacropeptide (GMP) from the surface of casein micelles. (engconfintl.org)
- Non-specific proteolysis of casein molecules by chymosin during this milk clotting process releases soluble peptides into the whey, resulting in protein losses from the cheese. (engconfintl.org)
- However, the homologous enzyme from Camelus dromedarius (camel chymosin) has been shown to be a superior alternative for various cheese types, since it reveals higher specific activity (C) and specificity (C/P) for the milk clotting reaction , as well as lower alphaS1 and beta casein proteolysis during ripening (Fig. 1). (engconfintl.org)
- Chymosin, a digestive enzyme from the stomach of a milk-fed calf, is exquisitely designed to provide the casein micelles a haircut (p. 57). (to-coachoutlet.com)