Enzyme Lysing

The present investigations, although limited to the local application of fibrolase, demonstrate that under these conditions the enzyme lyses venous or arterial thrombi rapidly and with no observable systemic or hematologic side effects. In these thrombosis model systems the enzyme, either alone or in combination with antiplatelet therapy, offers a unique, safe, and specific mechanism for clot dissolution and may prove useful as a clinically effective alternative to, or for use in synergistic combination with, presently used thrombolytic agents. 

Reverse transcriptase (from avian or murine RNA tumour viruses) [9068-38-6] [EC 2.7.7.49]. Purified by solubilising the virus with non-ionic detergent. Lysed virions were adsorbed on DEAE-cellulose or DEAE-Sephadex columns and the enzyme eluted with a salt gradient, then chromatographed on a phosphocellulose column and enzyme activity eluted in a salt gradient. Purified from other viral proteins by affinity chromatography on a pyran-Sepharose column. [Verna Biochim Biophys Acta 473 1 7977 Smith Methods Enzymol 65 560 1980 see commercial catalogues for other transcriptases.]... 

As shown in Figure 8.1a, the carrier binding method is based on binding microbial cells directly to water-insoluble carriers. The binding is due to ionic forces between the microbial cells and the water-insoluble carriers. This technique has rarely been used, however, because of lyses dming the enzyme reactions. Microbial cells may leak from the earner, thereby disrupting the immobilisation. Therefore, this method has not been applied successfully.6... 

There has been considerable discussion regarding the mode of action of the sea cucumber and starfish saponins. Both the triterpene and steroidal glycosides inhibit both Na/K ATPase and Ca/Mg ATPase 06) possibly as a result of their aglycone structures. However, their detergent properties cause membrane disruption which will influence the activity of membrane-bound enzymes such as the ATPases. In investigating the actions of saponins on multilamellar liposomes, it was found that cholesterol serves as the binding site for such saponins and that cholesterol-free lip-somes are not lysed by saponins 107). 

Mode of action Interferes with bacterial cell wall synthesis during active multiplication, causing cell wall death and resultant bactericidal activity Inhibits bacterial cell wall synthesis by binding to one or more of the penicillin-binding proteins, which in turn inhibit the final transpeptidation step of peptidoglycan synthesis in bacterial cell walls bacteria usually lyse from ongoing autolytic enzyme activity... 

Such clots—also known as emboli—present a serious hazard by their potential for blocking circulation of blood to vital organs. The considerable research devoted to agents that will lyse the fibrin in clots has led to the development of the clinically useful agent, uj-okinase. This drug is a fibrinolytic proteinaceous enzyme isolated from human urine. The difficulty involved in isolation of significant amounts and the antigenicity of urokinase and a related... 

Approximately 99.5% of saliva is water. Swallowing is facilitated by the moistening of food materials furthermore, it serves as a solvent for molecules that stimulate the taste buds. The presence of mucus, which is thick and slippery, lubricates the mouth and the food and assists in swallowing. Lysozyme is an enzyme that lyses or kills many types of bacteria that may be ingested. 

The temperate virus does not exist in its mature, infectious state inside the cell, but rather in a latent form, called the provirus or prophage state. In considering virulent viruses we learned that the DNA of the virulent virus contains information for the synthesis of a number of enzymes and other proteins essential to virus reproduction. The prophage of the temperate virus carries similar information, but in the lysogenic cell this information remains dormant because the expression of the virus genes is blocked through the action of a specific repressor coded for by the virus. As a result of a genetic switch, the repressor is inactivated, virus reproduction occurs, the cell lyses, and virus particles are released. 

There are two sources of biochemicals in soil one is the cellular constituents released when cells are destroyed during the extraction process. It should be kept in mind that any handling of a soil sample will cause the destruction of some of the cells it contains. The simple act of sieving, air drying, and weighing soil will cause some lyses of cells and release of their contents. Extraction will typically cause complete destruction of all cells in soil, with the release of all their constituent parts. Some parts such as enzymes may continue to function after release from the cell and continue to change the makeup of soil components for some time. 

Bioorganic components in soil include those organic molecules that participate in biochemical reactions, initiate reactions, inhibit the action of other biochemical, or act as antibiotics. Bioorganic chemistry also uses synthesized molecules to study biological processes such as enzyme activity. Often these studies are undertaken to develop a mechanism for the reactions of interest. Bioorganic molecules will be present either as components of the synthesis chain or as part of the degradation products. Whenever a cell lyses, its compounds will be released into the soil solution. 

A mutarotase is an enzyme that oata lyses the irtter-conversfon of alpha and beta forms of... 

Persons with mutations that partially destroy G6PDH activity may develop an acute, episodic hemolysis. Certain mutations affect the stability of G6PDH, and, because erythrocytes cannot synthesize proteins, the enzyme is gradually lost over time and older red blood cells lyse. This process is accelerated by certain drugs and, in a subset of patients, ingestion of fava beans. In the United States, the most likely cause of a hemolytic episode in these patients is overwhelming infection, often pneumonia (viral and bacterial) or infectious hepatitis. 

Reverse micelles of CTAB in octane with hexanol as cosurfactant were reported to be able to lyse whole cells quickly and accommodate the liberated enzyme rapidly into the water pool of surfactant aggregates [50,51]. In another case a periplasmic enzyme, cytochrome c553, was extracted from the periplasmic fraction using reverse micelles [52]. The purity achieved in one separation step was very close to that achieved with extensive column chromatography. These results show that reverse micelles can be used for the extraction of intracellular proteins. 

Many microorganisms produce enzymes that lyse the cell wall of yeast. The most extensive work has been done with the lytic system from Arthrobacter sp., Cytophaga sp., Oerskovia, Bacillus circulans, Rhizopus, Tri-choderma, Penicillium, Pellicularia sp., Rhizoctonia, and Streptomyces sp. (3-9). 

The activity of j8-glucuronidase at the usual pH of the transferase assays (pH 7.4r-8.2) is very low. The enzyme, most likely, has no role in the conjugation process itself (G4). If potentially important, e.g., in work with homogenates or cell extracts containing partially lysed lysosomes, the specific inhibitor saccharo-(l4)-lactone (L9) can be added to the incubation mixtures. 

Enzymes, specialized proteins, are used as designing tools for genetic engineering. One of these enzyme tools consists of restriction endonucleases that recognize a specific series of base pairs. They split the DNA at these specific points. This splitting is called lysing , which in reality is simply the hydrolysis of DNA units as shown in the following structure ... 

NTIOO Nair, U. ]., N. Ammigan, J. R. Kul-karni, and S. V. Bhide. Species difference in intestinal drug metabolising enzymes in mouse, rat and hamster and their inducibility by masheri, a pyro-lysed tobacco product. Indian J Exp Biol 1991 29(3) 256-258. 

Detergents. Under appropriate conditions of pH, ionic strength and temperature, detergents (ionic sodium lauiyl sulphate, sodium deoxycholate, sodium cholate and cetyldiethyl-ammonium bromide, or nonionic Tweens and Tritons), can be used to lyse cells. Detergents may however cause enzyme inactivation and may need to be removed before purification. 

Streptokinase is a protein (but not an enzyme in itself) synthesized by streptococci that combines with the proactivator plasminogen. This enzymatic complex catalyzes the conversion of inactive plasminogen to active plasmin. Urokinase is a human enzyme synthesized by the kidney that directly converts plasminogen to active plasmin. Plasmin itself cannot be used because naturally occurring inhibitors in plasma prevent its effects. However, the absence of inhibitors for urokinase and the streptokinase-proactivator complex permits their use clinically. Plasmin formed inside a thrombus by these activators is protected from plasma antiplasmins, which allows it to lyse the thrombus from within. 

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