Proteinase property

Factor VIII, immunoglobulin, and albumin are all held as protein precipitates, the first as cryoprecipitate and the others as the Cohn fractions FI + II + III (or FII + III) and FIV + V (or FV), respectively (Table 7, Fig. 2). Similarly, Fractions FIVj + FIV can provide an intermediate product for the preparation of antithrombin III and a-1-proteinase inhibitor. This abiUty to reduce plasma to a number of compact, stable, intermediate products, together with the bacteriacidal properties of cold-ethanol, are the principal reasons these methods are stiU used industrially. 

As these experiments with engineered mutants of trypsin prove, we still have far too little knowledge of the functional effects of single point mutations to be able to make accurate and comprehensive predictions of the properties of a point-mutant enzyme, even in the case of such well-characterized enzymes as the serine proteinases. Predictions of the properties of mutations using computer modeling are not infallible. Once produced, the mutant enzymes often exhibit properties that are entirely surprising, but they may be correspondingly informative. 

Subtilisins are a group of serine proteinases that are produced by different species of bacilli. These enzymes are of considerable commercial interest because they are added to the detergents in washing powder to facilitate removal of proteinaceous stains. Numerous attempts have therefore recently been made to change by protein engineering such properties of the subtilisin molecule as its thermal stability, pH optimum, and specificity. In fact, in 1988 subtilisin mutants were the subject of the first US patent granted for an engineered protein. 

Craig JC, Duncan IB, Hockley D, Grief C, Roberts NA, Mills JS (1991) Antiviral properties of Ro 31-8959, an inhibitor of human immunodeficiency virus (HIV) proteinase. Antiviral Res 16 295-305... 

Wong, P.S. and Travis, J. (1980). Isolation and properties of oxidised alpha-l-proteinase inhibitor from human rheumatoid synovial fluid. Biochem. Biophys. Res. Commun. 96, 1449-1454. 

Konarev AV, Anisimova IN, Gavrilova VA, et al. Serine proteinase inhibitors in the Compositae distribution, polymorphism and properties. Phytochemistry 2002 59 279-291. 

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... 

Riichel R (1981) Properties of a purified proteinase from the yeast Candida albicans. Biochim Biophys Acta 659, 99-113. 

Casein may be coagulated and recovered as rennet casein by treatment of milk with selected proteinases (rennets). However, one of the caseins, K-casein, is hydrolysed during renneting and therefore the properties of rennet casein differ fundamentally from those of acid casein. Rennet casein, which contains the colloidal calcium phosphate of milk, is insoluble in water at pH 7 but can be dissolved by adding calcium sequestering agents, usually citrates or polyphosphates. It has desirable functional properties for certain food applications, e.g. in the production of cheese analogues. 

Penicillium caseicolum produces an extracellular aspartyl proteinase and a metalloproteinase with properties very similar to those of the extracellular enzymes produced by P roqueforti (Trieu-Cout and Gripon 1981 Trieu-Cout et al. 1982). Breakdown of casein in mold-ripened cheese results from the synergistic action of rennet and the proteases of lactic streptococci and penicillia (Desmazeaud and Gripon 1977). Peptidases of both lactic acid bacteria and penicillia contribute to formation of free amino acid and nonprotein nitrogen (Gripon et al. 1977). 

Dresden, M.H., Rutledge, M.L. and Chappell, C.L. (1981) Properties of the acid thiol proteinase from Schistosoma mansoni adults. Molecular Biochemical Parasitology 4, 61-65. 

Lazebnik, Y.A., Kaufmann, S.H., Desnoyers, S., Poirier, G.G. and Eamshaw, W.C. (1994) Cleavage of poly(ADP-ribose) polymerase by a proteinase with properties like ICE. Nature, 371, 346-347. 

Nemova, N.N. (1991). Properties and the physiological role of intracellular proteinases in fish tissues (In Russian). Uspekhi Sovremennoy Biologii 111, 948-954. 

LaMarre J, Wollenberg GK, Gonias SL, Hayes MA. Cytokine binding and clearance properties of proteinase-activated alpha 2-macroglobulins. Lab Invest 1991 65(1)3-14. 

In order to obtain further information about the primary specificity of aspergillopepsin I, we constructed an aspergillopepsin I expression system in Escherichia coli, prepared mutants at positions 76 and 78 of aspergillopepsin I by site-directed mutagenesis, and compared then-molecular and enzymatic properties [30], We showed that the nature of the active site flap is important for deciding the Si substrate specificity of aspartic proteinases [30],... 

Pepsin (EC 3.4.23.1) is a typical aspartic proteinase produced in the gastric mucosa of vertebrates as a zymogen form [10], This enzyme has been extensively characterized, and its three-dimensional structure has been determined at high resolution. Porcine pepsin, in particular, has been studied as model to analyze the structure-function relationship of the aspartic proteinases. Although the aspartic proteinases including mammalian and fungal enzymes are quite similar in their three-dimentional structures, there are drastic differences in the catalytic properties, especially in substrate specificities. 

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