Browning proteolytic

It is noteworthy that several of fhe above-mentioned mediators of discoloration have been found fo inhibif sfrepfococcal proliferation. In addition, collagen cross-linking caused by enzymatic and non-enzymat-ic browning or by tannage with tannins might render dentin less susceptible to proteolytic degradation. 

Brown, M.S., Goldstein, J.L. (1999) A proteolytic pathway that controls the cholesterol content of membranes, cells, and blood. Proc. Natl. Acad. Sci. USA 96, 11,041-11,048. 

Linklater (1961) reported that bovine pepsin accounted for only 0 to 6% of the milk-clotting activity of commercial rennet extracts. He used porcine pepsin as a reference standard. Bovine pepsin has increased in use as a coagulant because of the practice of extracting the stomach from older calves and adult cattle. More recently, Sellers (1982) reported that 85 to 95% of the proteolytic activity of calf rennet is due to chymosin and the remainder is from bovine pepsin. Adult bovine rennets preparations may contain 55 to 60% bovine pepsin. Mixtures of calf rennet and porcine pepsin may contain 40 to 45% chymosin, 5 to 10% bovine pepsin, and 50% porcine pepsin. Mixtures of adult bovine rennet and porcine pepsin typically contain 20 to 25% chymosin, 40 to 45% bovine pepsin, and 30 to 40% porcine pepsin activity (McMahon and Brown 1985). 

Shaker, K. A. and Brown, R. J. 1985B. Proteolytic and milk clotting fractions in milk clotting preparations. J. Dairy Sci. 68, 1939-1942. 

Ficin The purified proteolytic substance derived from the latex of Ficus sp. (Fam. Moraceae), which include a variety of tropical fig trees. Produced as a white to off white powder completely soluble in water. (Liquid fig latex concentrates are light to dark brown.) Major active principle ficin. Typical applications used in the chillproofing of beer, in the tenderizing of meat, and in the conditioning of dough in baking. 

OH)2D3-mediated phosphorylation [67]. In the case of PKC, 1,25-(OH)2D3 causes translocation of PKC-/ to the plasma membrane and PKC-a to the nucleus [269-271], Both PKC iso types are calcium-dependent, and l,25-(OH)2D3 does not affect the calcium-independent PKC-f [271], Brown and DeLuca [272] demonstrated that VDR phosphorylation is rapid, occurring within 1 h following treatment of l,25-(OH)2D3 of embryonic chick duodenal organ culture. In addition, phosphorylation occurred before calcium uptake and the 1,25-(OH)2D3-dependent increase in calcium-binding protein mRNA. Proteolytic digestion of the l,25-(OH)2D3-dependent phosphorylation of porcine VDR was mapped and shown to be localized to a 23 Kd fragment of the C-terminal domain [273]. 

Contrary to expectations that fungal diseases would lead to elevated levels of PR proteins in berries, Marchal et al. (1998) observed that juice from berries infected by B. cinerea showed reduced protein levels, and suggested that proteolytic enzymes from B. cinerea were responsible for this. Secretion of proteases by B. cinerea has been observed in culture media and on fruits such as apple (Zalewska-Sobczak et al. 1981) and tomato (Brown and Adikaram 1983). Girbau et al. (2004) also examined the impact of infection of grapes with B. cinerea in the vineyard and showed that infection resulted in marked decreases in the levels of PR proteins in... 

SREBP resides in the endoplasmic reticulum, where it is bound to SCAP by its regulatory (Reg) domain. When cholesterol levels fall, SCAP and SREBP move to the Golgi complex, where SREBP undergoes successive proteolytic cleavages by a serine protease and a metalloprotease. The released DNA-binding domain moves to the nucleus to alter gene expression. [After an illustration provided by Dr. Michael Brown and Dr. Joseph Goldstein.]... 

Pancreatin is described in the different pharmacopeia as a slightly brown, amorphous powder with a faint, characteristic odor. It is slowly and incompletely soluble in water it is not recommended to filter the solution as the lipolytic enzymes and part of the proteolytic activity may be retained on the filter. Most pharmacopeia stipulate the minimum units of amylase (12,000 FIP units/g), lipase (15,000 FIP units/g), and protease (1000 FIP units/g) activity, but give no specifications on the content of the other components such as phospholipase A2, carboxylester lipase, colipase, and individual proteolytic enzymes. It... 

Hnng GC, Brown CR, Wolfe AB, Lin J, Chiang HL. (2004). Degradation of the gluconeogenic enzymes fmctose-l,6-bisphosphatase and malate dehydrogenase is mediated by distinct proteolytic pathways and signaling events. J Biol Chem, 279, 49138 9150. 

Rinse gel briefly with water, place in gel fixing solution, and finish by staining gel with Coomassie blue. Proteolytic activity is indicated by clearing zones on blue background. For representative examples see Heussen and Dowdle (1980) and Brown et al. (1990). 

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