And proteinase activity

Langsford et al. reported that Cellulomonas fimi culture supernatants contained cellulase and proteinase activities, for which there appeared to be a relationship. Glucose repressed the synthesis of both activities and cellulose induced both 60), Adding cellulose to Cellulomonas sp. (NRCC 2406) cultures stimulated growth and improved production of cellulases 61). Optimum conditions for growth and cellulase production were pH 6.5 and 30 C. The addition of glucose in the presence of cellulose inhibited growth. Several species of Cellulomonas have cellobiose phosphorylase. 

Efstathiou, J. P. and McKay, L. L. 1976. Plasmids in Streptococcus lactis Evidence that lactose metabolism and proteinase activity are plasmid linked. Appl. Environ. Microbiol. 32, 38-44. 

Garcfa-Carreno, F.L., Herandez-Cortes, M.P., and Haard, N.F. 1994. Enzymes with peptidase and proteinase activity from the digestive systems of freshwater and a marine decapod. J. Agric. Food Chem. 42 1456-1461. 

Wallenfels and Pechmann (1951) were able to separate from a technical enzyme preparation amylase, lipase, phosphatase, and proteinase activities. 

Little is known about the chemical nature of hypertensinase. The enzyme was not precipitated by dialysis. In fractionation experiments it was found in the fraction precipitated between 30 and 60% saturation with ammonium sulfate. In a comparative study of hypertensinase and proteinase activity of blood plasma (30,31), there was found in various plasma fractions a parallel between hypertensinase activity and hydrolyzing effect on Z-leucylglycine. These findings were interpreted as supporting evidence for the hypothesis that plasma hypertensinase active at pH 7.3 to 7.8 is an aminopeptidase. 

Proteinase-activated recqrtors (PARs) are a unique family of G-protein-coupled receptors (GPCRs) that are activated in response to serine proteinases. There are four PAR family members PAR-1 through to PAR-4. PAR-1 and PAR-3 respond to thrombin, PAR-2 responds to trypsin, whilst PAR-4 is sensitive to both thrombin- and trypsin-related proteinases. 

Proteinase-activated Receptors. Figure 1 Activation of proteinase-activated receptors (PARs) through proteolytic cleavage with serine proteinases (1) and independent of cleavage though PAR-specific activating peptides (2). 

Proteinase-activated Receptors. Table 1 Proteinase, peptide and non-peptide modulators of PAR activation... 

In some cases, receptor inactivation, e.g., of the V2 vasopressin receptor, is mediated by agonist-induced enzymatic cleavage of the GPCR. This nonendocytic proteolysis is promoted by a plasma membrane-associated metalloprotease. Proteinase-activated receptors (PARs) such as the thrombin receptor also follow a distinctly different pathway. PARs require the enzymatic cleavage of their N terminus, and the newly generated N terminus activates the receptor. Once... 

Trypsin is a major proteolytic digestive enzyme and the identified endogenous ligand for proteinase-activated receptor 2 (PAR 2). 

Eosinophils may be increased in some patients, particularly during exacerbations. Activated inflammatory cells release a variety of mediators, most notably leukotriene B4, interleukin-8, and tumor necrosis factor-a (TNF-a). Various proteinases, such as elastase, cathepsin G, and proteinase-3, are secreted by activated neutrophils. These mediators and proteinases are capable of sustaining inflammation and damaging lung structures. 

Proteinases and antiproteinases are part of the normal protective and repair mechanisms in the lungs. The imbalance of proteinase-antiproteinase activity in COPD is a result of either increased production or activity of destructive proteinases or inactivation or reduced production of protective antiproteinases. AAT (an antiproteinase) inhibits trypsin, elastase, and several other proteolytic enzymes. Deficiency of AAT results in unopposed proteinase activity, which promotes destruction of alveolar walls and lung parenchyma, leading to emphysema. 

Other plasminogen activator inhibitors are PAI-3, which is believed to be identical to the activated protein C inhibitor, and proteinase nexin 1, found in the renal epithelial cells, cytosol of fibroblasts, and cardiac myocytes (37, 42, 44, 45). 

Female NMRI mice were exposed to 100 ppm of hydrogen sulfide for 2 hours at 4-day intervals excitement was observed (Savolainen et al. 1980). Exposure also resulted in decreased cerebral ribonucleic acid (RNA), decreased orotic acid incorporation into the RNA fraction, and inhibition of cytochrome oxidase. An increase in the glial enzyme marker, 2, 3 -cyclic nucleotide-3 -phosphohydrolase, was seen. Neurochemical effects have been reported in other studies. Decreased leucine uptake and acid proteinase activity in the brain were observed in mice exposed to 100 ppm hydrogen sulfide for 2 hours (Elovaara et al. 1978). Inhibition of brain cytochrome oxidase and a decrease in orotic acid uptake were observed in mice exposed to 100 ppm hydrogen sulfide for up to 4 days (Savolainen et al. 1980). 

In an earlier report (J>), the decay of healthy yam tubers during storage was shown to be a result of catabolism of its proteins by an active a-glutamyl transpeptidase. There is also some alkaline proteolytic activity in the yam tuber (6), but little information is available on individual enzymes of the purine degradative pathway and on the properties of an alkaline proteinase that may function in yams during storage. This report describes the interrelation of five enzymes of ureide metabolism in fresh and stored yams, the release of ammonia in vitro by three of the enzymes that may provide an environment for alkaline proteinase activity in vivo, and the in vitro properties of an... 

Alkaline Proteinase Activity in Yams. The release of ammonia at several stages during ureide metabolism suggested a potential for alkaline conditions in yam tubers, rather than the usual neutral or acid conditions generally found in seeds and plants. 

Because yams are stored in open systems at ambient temperatures (usually warm), tuber tissue was examined for proteinase activity at 40°C. Some tubers had high apparent polyphenol oxidase activity upon peeling of the tubers (tissue turned deep purple at the peeled surface) so that PYP was added to extracts to combine with polyphenolic compounds and protect the proteinase from reacting with these compounds. Earlier studies had shown some inhibition of alkaline proteinase activity by ferric ion (24) so that EDTA was also added to the extracts to chelate any free iron. Two alkaline pH optima were found, at 9.0 and 10.5. The alkaline proteinases of white potatoes (Solanum tuberosum) have pH optima between 8.6 and 9 (25) and those of Carilla chocola tubers have pH optima between 8.0 and 9.5 (26,27T, suggesting that alkaline... 

Removal of the N- and C-terminal propeptides from fully folded procollagens occurs only after transport of procollagens across the Golgi stacks and results in collagen molecules that are then able to assemble into fibrils. C-proteinase activity is possessed by members of the tolloid family of zinc metalloproteinases,... 

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