Mucor pusillus

Babel, F. J. and Somkuti, G. A. 1968. Mucor pusillus protease as a milk coagulant for cheese manufacture. J. Dairy Sci. 51, 937-937. 

Richardson, G. H., Nelson, J. H., Lubnow, R. E. and Schwarberg, R. L. 1967. Rennin-like enzyme from Mucor pusillus for cheese manufacture. J. Dairy Sci. 50, 1066-1072... 

Beppu, T., Park, Y.-N., Aikawa, J., Nishiyama, M., and Horinouchi, S. (1995). Tyrosine 75 on the flap contributes to enhance catalytic efficiency of a fungal aspartic proteinase, Mucor pusillus pepsin. In Aspartic Proteinase Structure, Function, Biology, and Biomedical Implications. Takahashi, T. (Ed.), (pp. 559-563). New York Plenum Press. 

Tam, J.T., Whitaker, J.R. 1972. Rates and extents of hydrolysis of several caseins by pepsin, rennin, Endothia parasitica and Mucor pusillus proteinase. J. Dairy Sci. 55, 1523-1531. 

The use of other acid proteases as substitutes for rennin in cheese making is determined by whether bitter peptides are formed during ripening of the cheese and by whether initial rapid hydrolysis causes excessive protein losses in the whey. Some of the acid proteases used in cheese making include preparations obtained from the organisms Endo-thia parasitica, Mucor miehei, and Mucor pusillus. Rennin contains the enzyme chy-mosin, and the scarcity of this natural enzyme preparation for cheese making resulted in the use of pepsin for this purpose. Pepsin and chymosin have primary structures that have about 50 percent homology... 

Garlic has in vitro antifungal effects against Cryptococcus neoformans, Candida spp., Trichophyton, Epidermophyton, Microsporum, Aspergillus spp., and Mucor pusillus (40). When five volunteers consumed 10-25 mL of fresh garlic extract, urine samples had antifungal activity, but susceptibility from serum samples dropped significantly (42). 

Although the general proteolytic activities of various milk clotting enzymes may vary, their milk clotting activities are apparently predicated on the same specific cleavage of the Phe-Met bond in -casein. Apparently rennin, pepsin, chymotrypsin, a microbial protease, proteases from Endo-thia parasitica, Mucor pusillus, and Mucor miehei exert the same type of activity on -casein (2, 169). Enzymes that are currently used commercially for cheesemaking in the United States include rennin, rennin-pepsin mixtures, and microbial proteases from Endothia parasitica, Mucor pusiUus, and Mucor miehei. 

The proteases currently used as coagulants in the cheese industry are known to proteolyze the various casein components. Rennin, porcine pepsin, and proteases from Endothia parasitica, Mucor miehei, and Mucor pusillus readily attack 8-> / -, and K-caseins (195, 199). 

History, Use and/or Medical Implications Some species toxic. Mucor pusillus and other mu-curaceous fungi are the cause of a rare but deadly disease known as mucormycosis or phycomy-cosis. Although Mucor attacks open wounds, the outer ear and the lungs, it is not a primary parasite but one that takes advantage of poor health caused from other diseases. This disease and ones related to it are more prevalent in tropical and semitropical zones than in temperate regions. For... 

Rennet is used extensively in the production of cheese. This enzyme is found in the fourth stomach of the calf it converts casein into paracasein, which, in the presence of calcium, precipitates to form an elastic curd. Much commercial rennet is contaminated with pepsin which tends to act strongly on casein and thereby produces a weak curd with off flavor. Many microbial proteases can clot milk, but only recently have microbial preparations been produced which can replace calf rennet to prepare cheeses of good flavor. Microbial preparations from Endothia parasitica and Mucor pusillus var. Lindt seem to be the most promising, and these have been used commercially. The new sources of rennet were reviewed recently (Sardinas, 1969). 

Mucor pusillus [26] Milk-clotting enzymes, lipase... 

Hiramatsu R, Aikawa J, Horinouchi S et al. (1989) Secretion by yeast of the zymogen form of Mucor rennin, an aspattic proteinase of Mucor pusillus, and its conversion to the mature form. The J Biol Chem 264(28) 16862-16866... 

MIlk-clotting enzyme from Mucor pusillus 977017-76-7... 

Adams, P. R., 1981, Amylase Production by Mucor Pusillus and Humicola Lanuginosa as Related to Mycelial Growth, Mycopathologla, 76 97. 

Central to the study of mechanism and specificity of the acid proteinases is a knowledge of the three-dimensional structures of enzymes with different physiological roles. The availability of acid proteinases with either extracellular or intracellular roles in vertebrates as well as similar enzymes from plants, protozoa, and fungi allows a wide range of comparative studies. In our laboratory we have undertaken the x-ray analysis of fungal enzymes, those from Endothia parasitica and Mucor pusillus, and some vertebrate enzymes including chymosin and chicken pepsin, and are beginning work with cathepsin D. 

We also have crystals of chymosin (6), the acid proteinase from Mucor pusillus (7), chicken pepsin (8), and chicken pepsinogen (8), the first two of which are large and very suitable for x-ray analysis. Dr. C. W. Bunn and his co-workers made preliminary x-ray studies of chymosin but the method of isomorphous replacement was unsuccessful, as simple heavy atom derivatives proved impossible to prepare. Both we and Professor B. Foltmann and Dr. S. Larsen of Copenhagen have continued x-ray studies on chymosin, but have also met difficulties. More recently, we have began to use the structural information from the Endothia parastica enzyme to solve the structure of chymosin by using the method of molecular replacement. 

Similar use of molecular replacement combined with refinement at high resolution appears to be the most hopeful method of defining the molecular structures of the enzymes from Mucor pusillus and chicken pepsin. 

Rennets Bacillus polymyxa Bacillus subtilis Endothia parasitica Mucor miehei Mucor pusillus As coagulants in cheese curd making. 

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