Enzyme elastases

In this method, ai-antiproteinase inhibits the hydrolytic enzyme elastase, and the remaining elastase activity is measured by monitoring increases in absorbance at410 nm. Martmez-Tome and others (2001) used a method based on this reaction to measure the antioxidant activity of broccoli amino acids and of Mediterranean spices. 

The separateness of two domains within a subunit varies all the way from independent globular domains joined only by a flexible length of polypeptide chain, to domains with tight and extensive contact and a smooth globular surface for the outside of the entire subunit, as in the proteolytic enzyme elastase (fig. 4.20). An intermediate level of domain separateness, characterized by a definite neck or cleft between the domains, is found in phosphoglycerate kinase (fig. 4.21). 

Angiotensin I converting enzyme Acquired immunodeficiency syndrome Aspartic protease inhibitor Bowman Birk protease inhibitor protein Chymotrypsin Cysteine protease inhibitor Endothelin-converting enzyme Elastase... 

Some people have a genetic predisposition to emphysema. This is called familial emphysema. These individuals have been found to have a genetic defect in the gene that encodes the human plasma protein Uj-antitrypsin. As the name suggests, Ui-antitrypsin is an inhibitor of the proteolytic enzyme trypsin. But, as we have seen in this chapter, trypsin is just one member of a large family of proteolytic enzymes called the serine proteases. In the case of the oii-antitrypsin activity in the lung, it is the inhibition of the enzyme elastase that is the critical event. 

Cigarette smoke attracts inflammatory cells into the lungs and stimulates the release of the proteolytic enzyme elastase. Elastase breaks down elastin, which is a needed structural component of lung tissue. Normally, the lung is protected from elastase by an inhibitor, ai-antitrypsin (ATT). Cigarette smoke, however, causes an abnormal amount of elastase to be produced that ATT... 

Describe the steps required for synthesis of the enzyme elastase and its preparation for export from the cell. 

Pulmonary emphysema is a chronic progressive disorder wherein the elastic fibers of the lung become fragmented and dysfunctional with the result of a loss of elastic recoil. One result is that the patient must consciously and forcibly exhale. A prominent proposal for the etiology of the disease has been the lack of proteinase inhibitors that would otherwise prevent proteolytic degradation of the fiber.To help study the disease, a successful animal model for pulmonary emphysema was developed in which direct instillation of the proteolytic enzyme elastase into the lung became the causative agent. ° ... 

An interesting data seen in the degeneration of the cartilage of ligaments, tendons, and bone structures, besides that of elastic fibers, is that the enzyme elastase that plays a role in these pathologies increases its activity with aging. 

The peptide substrate is hydrolyzed by the enzyme elastase by the same mechanism as for chymotrypsin. However, here the pocket is closed to such an extent by the side chains of Val and Thr that only the methyl group of alanine can enter the cleft (Fig. 2.11c). Therefore, elastase has specificity for alanyl peptide bonds or alanyl ester bonds. 

Betulinic acid (316), also known as 3(3-hydroxy-lup-20(29)-en-28-oic acid 3(3-hydroxy-lup-20(29)-en-28-oic acid mairin (+)-betulinic acid (3-betulinic acid 3 P-Hydroxylup-20(29)-en-28-oic acid betulic acid or lupatic acid, is present in and extracted from the bark of the White Birch Betula alba). Betulinic acid has anticancer properties that have been reviewed by Eiznhamer and Xu (384). Betulin (317) and betulinic acid also possess activities that are useful in the field of cosmetics. They inhibit the enzyme elastase thus correcting loss of skin elasticity stimulate collagen synthesis are antiinflammatory, and inhibit melanogenesis. The resultant market need is filled by use of purified bark extract [84012-15-7], rich in both triterpenes. 

Neutrophils also contain several cationic serine proteases (5). The enzyme, elastase, is particularly abundant The amount of elastase contained in the granules of a single neutrophil is in excess of one picogram (4) Several groups have used specific inhibitors as well as antisera to demonstrate that elastase or an elastase-like protease is abundant in chronic wound fluids (13,22-24). Mean levels of elastase activity is approximately 12-fold higher in fluids of chronic dermal ulcers compared to surgical... 

It has been demonstrated in vitro that flavonoids inhibit a number of enzymes (elastase, hyaluronidase, cAMP phosphodiesterase, 5-Iipooxygenase, cyclooxygenase, etc.). Quercetin, rutin, myricetin, kaanpferol and morin inhibit the 5-Iipooxygenase enzyme. Quercetin also inhibits the 12-Upooxygenase and the cyclooxygenase enzymes. Flavones inhibit the phospholipase A2 enzyme and can be used as anti-inflammatory and antiirritant agent. 

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