Ribonuclease Optimized Blend

Catalog Number E5904 Storage Temperature –20 °C

Ribonuclease A RNase T1 from Aspergillus oryzae is an (EC 3.1.27.5 and CAS RN 9001-99-4) that hydrolyzes after G residues. In Ribonuclease T1 the reaction, cleavage occurs between the (EC 3.1.27.3 and CAS RN 9026-12-4) 3¢-phosphate group of a guanidine ribonucleotide and the 5¢-hydroxyl group of the adjacent nucleotide. The Product Description initial product is a 2¢:3¢ cyclic phosphate that is This product is an optimized blend of Ribonuclease A hydrolyzed to the corresponding 3¢-nucleoside 8 (RNase A) from bovine pancreas and Ribonuclease T1 phosphate. from Aspergillus oryzae. The molecular masses based upon the sequences are 13.7 kDa and 1,2 The product is supplied as a ready-to-use solution in 11.088 kDa, respectively. 50 mM sodium acetate, pH 5.0, containing 0.3 mM EDTA and 50% glycerol. This optimized blend combines ribonuclease with different substrate specificities to give a product Precautions and Disclaimer that cleaves RNA more efficiently than either This product is for R&D use only, not for drug, alone. The product is free of DNase and protease household, or other uses. Please consult the Material impurities and is suitable for rapid digestion of RNA in Safety Data Sheet for information regarding hazards plasmid DNA preparations (0.1–0.5 units [1–5 ml] for a and safe handling practices. typical 5 minute mini-prep treatment), RNA protection, and RT-PCR applications. The product is sold on the Storage/Stability basis of RNase A acitivity (Kunitz units). The product ships on wet ice and storage at –20 °C is recommended. RNase A is an endoribonuclease that cleaves at the 3¢-phosphate of a pyrimidine (U or C) nucleotide. The References sequence of pG-pG-pC-pA-pG will be cleaved to give 1. Smyth, D.G. et al., J. Biol. Chem., 238, 227-234 pG-pG-pCp and A-pG. The highest activity is exhibited (1963). 3 with single stranded RNA. It is a single chain 2. Takahashi, K., J. Biochem. Japan, 70, 945-960, polypeptide containing 4 disulfide bridges. In contrast to (1971). 4 RNase B, it is not glycosylated. RNase A can be 3. Burrell, M.M., Enzymes of Molecular Biology, 16, 12 119 inhibited by alkylation of His or His present in the 263-270 (1993). 5 active site of the enzyme. Activators of RNase A 4. Plummer, T.H., and Hirs, C.H.W., J. Biol. Chem., include potassium and sodium salts. The optimal 238, 1396-1397 (1963). temperature for activity is 60 °C, although the enzyme 5. Heinrikson, R.L. et al., J. Biol. Chem., 240, 2921- exhibits activity from 15–70 °C. The pH optimum is 7.6, 2934 (1965). with activity observed in the pH range of 6–10.6 6. Enzyme Handbook, 3, Schomberg, D., and RNase A is a very stable enzyme and can withstand Salzmann, M., eds., Springer-Verlag (Berlin:1991), exposure to temperatures up to 100 °C. At 100 °C, pp 1-3 under E.C. 3.1.27.5. RNase A is most stable between pH 2.0 and 4.5.7 7. Crestfield, A.M. et al., J. Biol. Chem., 238, 618-621 (1963). 8. Uchida, T., and Egami, F., in The Enzymes, IV, Boyer, P.D., ed., Academic Press (New York, NY: 1971), pp 205-250.

RBG/MAM 01/10-1

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