Proteases neutral

Thermolysin belongs to a class of proteases (called neutral proteases) which are distinct from the serine proteases, sulfhydryl proteases, metal-loexopeptidases, and acid proteases. Neutral proteases A and B from Bacillus subtilis resemble thermolysin in molecular weight, substrate specificity, amino acid content, and metal ion dependence. Since physiological substrates are most likely proteins, it is difficult to design simple experiments that can be interpreted in terms of substrate specificity and relative velocities. Therefore, studies of substrate specificity and other kinetic parameters must be carried out on di- and tripeptides so that details of the mechanism of catalysis can be obtained and interpreted simply. 

The enzymes are as follows A, lipase B, hemicellulase C, pectin methylesterase D, protease. Neutral guar used (Supercol from Hercules Incorporated). 

Protease, neutral Origin Bacillus amyloliquefaciens Novozymes Neutrase ... 

Protease, neutral to acidic Origin Fungus Novozymes NovoCor P... 

S. protease, serine protease N. protease, neutral protease... 

Metabolic Functions. Zinc is essential for the function of many enzymes, either in the active site, ie, as a nondialyzable component, of numerous metahoenzymes or as a dialyzable activator in various other enzyme systems (91,92). WeU-characterized zinc metahoenzymes are the carboxypeptidases A and B, thermolysin, neutral protease, leucine amino peptidase, carbonic anhydrase, alkaline phosphatase, aldolase (yeast), alcohol... 

The enzymatic hydrolysates of milk casein and soy protein sometimes have a strong bitter taste. The bitter taste is frequently developed by pepsin [9001 -75-6] chymotrypsin [9004-07-3] and some neutral proteases and accounted for by the existence of peptides that have a hydrophobic amino acid in the carboxyhc terminal (226). The relation between bitter taste and amino acid constitution has been discussed (227). 

If the yeast does not get enough free amino nitrogen, the fermentation will be poor and the beer quaHty inferior. A neutral bacterial protease added at mashing-in can be used to raise the level of free amino nitrogen. This is useful when working with poorly modified malt or with high adjunct ratios. 

Mammals, fungi, and higher plants produce a family of proteolytic enzymes known as aspartic proteases. These enzymes are active at acidic (or sometimes neutral) pH, and each possesses two aspartic acid residues at the active site. Aspartic proteases carry out a variety of functions (Table 16.3), including digestion pepsin and ehymosin), lysosomal protein degradation eathepsin D and E), and regulation of blood pressure renin is an aspartic protease involved in the production of an otensin, a hormone that stimulates smooth muscle contraction and reduces excretion of salts and fluid). The aspartic proteases display a variety of substrate specificities, but normally they are most active in the cleavage of peptide bonds between two hydrophobic amino acid residues. The preferred substrates of pepsin, for example, contain aromatic residues on both sides of the peptide bond to be cleaved. 

Fig. 30. Chromatographic separation of 1) acid and 2) neutral proteases (Bac. Subtilis) on Biocarb-T biosorbent. A. proteolytic activity units/ml —o— B. protein concentration (E28o) — —...

Inhibition of inflammatory cytokines (Fig. 2) Humanized monoclonal anti-TNF antibodies (Infliximab (Remicade ), Adalimumab (Humira )) bind with high selectivity to human TNF-a and neutralize its activity. Thereby, infliximab decreases the effects of enhanced TNF levels during inflammatory disease such as production of proteases, chemokines, adhesion molecules, cyclooxygenase products (prostaglandins), and proinflammatory molecules such as interleukin-1 and -6. The antibodies may also recognize membrane-bound TNF-a on lymphocytes and other immune cells. These cells may subsequently become apoptotic or are eliminated via Fc-receptor-mediated phagocytosis. 

ET-1 from big-ET-1 by other proteases such as neutral endopeptidase or other currently unidentified proteases. Therefore, dual inhibition of ECE and NEP might inhibit ET-l generation more efficiently, than that seen for selective ECE inhibitors. However, dual inhibiton of ECE and NEP could also increase the risk for the development of AD, as both enzyme classes are involved in the degradation of A 3 peptide. 

Kaartinen M, Penttila A, Kovanen PT Accumulation of activated mast cells in the shoulder region of human coronary atheroma, the predilection site of atheromatous rupture. Circulation 1994 90 1669. Kaartinen M, Penttila A. Kovanen PT Mast cells of two types differing in neutral protease composition in the human aortic intima. Demonstration of tryptase- and tryptase/chymase-containing mast cells in normal intimas, fatty streaks, and the shoulder region of atheromas. Arterioscler Thromb 1994 14 966. 

These proteins are called acute phase proteins (or reactants) and include C-reactive protein (CRP, so-named because it reacts with the C polysaccharide of pneumococci), ai-antitrypsin, haptoglobin, aj-acid glycoprotein, and fibrinogen. The elevations of the levels of these proteins vary from as little as 50% to as much as 1000-fold in the case of CRP. Their levels are also usually elevated during chronic inflammatory states and in patients with cancer. These proteins are believed to play a role in the body s response to inflammation. For example, C-reactive protein can stimulate the classic complement pathway, and ai-antitrypsin can neutralize certain proteases released during the acute inflammatory state. CRP is used as a marker of tissue injury, infection, and inflammation, and there is considerable interest in its use as a predictor of certain types of cardiovascular conditions secondary to atherosclerosis. Interleukin-1 (IL-1), a polypeptide released from mononuclear phagocytic cells, is the principal—but not the sole—stimulator of the synthesis of the majority of acute phase reactants by hepatocytes. Additional molecules such as IL-6 are involved, and they as well as IL-1 appear to work at the level of gene transcription. 

The neutral azetidin-2-one 23 (Fig. 11.13), which has neither the latent leaving group northecarboxy substituent of the previous acidic azetidinone21, is a substrate of both HLE and PPE. Its functionalized analogue 24a inactivates these proteases by an... 

Water molecules or anions close to the active sites in the protease enzymes, mentioned above, may not be considered circumstantial, but may effectively contribute to the removal of the surplus proton from the imidazolium cation before the actual catalytic event. They could serve well to create the initial ion/neutral form of the Aspl02-His57 couple which is important for the initial step of the catalytic process in most discussions 11611 .13i. such a proton removal may be caused by the productive binding of a true substrate (or inhibitor) of the enzyme to the neighboring recognition clefts of the active site. 

Descaling by application of a heat-resistant neutral protease to confer a cashmere-like feel. 

Papain and four protease formulations that varied from neutral to alkaline as regards optimal pH for activity. 

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