RIBONUCLEASE A
Opis
≥50 Kunitz u/mg
Molecular Weight: 13,700
Physical Description: White lyophilized powder
Source: Bovine pancreas
Composition: The composition and structure of ribonuclease A has been extensively investigated. The tertiary structure indicates that flexibility in a three-dimensional structure is essential for optimal catalytic activity. (2,3,4)
Optimum pH: 7.0 - 7.5 (5)
Extinction coefficient: E1%280 = 7.3
Isoelectric point: pH 9.45 (6)
Specificity: The enzyme is specific for pyrimidine nucleoside linkages, i.e., those cleaving cyclic 2',3'-pyrimidine nucleotide residues either singly or at the termination of purine nucleotide chains. (7)
Inhibitors: Ribonuclease is inhibited by heavy metal ions and is competitively inhibited by DNA. The effect of denatured DNA is much greater than that of the native nucleic acid. (8)
Stability: The enzyme is stable for years stored as a refrigerated dry powder or frozen in solution; refrigerated solutions are stable for weeks. The enzyme aggregates upon lyophilization and storage. (9) Special care should be given to handling of the enzyme because of its affinity for glass surfaces (10)
Unit Definition: That amount of enzyme causing the hydrolysis of RNA at a rate such that k (velocity constant) equals unity at 25oC and pH 5.0.
Non-specific protease activity: Not detectable.
Purity: >70%
Solubility: Dissolves readily at 2 mg/ml in analytical grade water to give a clear colorless solution.
Dane techniczne
Opakowanie | 100 mg |