Enzymes : Deoxyribonuclease (Pancreatic dornase) and Streptokinase

Significance of the Enzyme Deoxyribonuclease (Pancreatic dornase)

English: Dornase Alfa, also known as Pulmozyme, a commonly inhaled treatment amongst CF patients. (Photo credit: Wikipedia)

is a nucleolytic enzyme and is prepared by fractional precipitation of aqueous acid extracts of beef pancreas, which is followed by dialysis, sterilisation by filtration and freeze drying. Pancreatic dornase is a white powder, soluble in water. It is stable in dry form and losses its activity in solution. The maximum activity is exhibited at pH 6-7. For its activity magnesium ions are required.

Medicinal Uses of Deoxyribonuclease:

It is used in the treatment of local abscesses and haematomas. It is used in the form of aerosols for reducing the viscosity of pulmonary secretions. It also enhances the expectoration of sputum in bronchopulmonary infections.

Significance of the Enzyme Streptokinase

Streptokinase is an enzyme which is obtained from the culture filtrates of beta-hemolytic Streptococci group C. Streptokinase activates human plasminogen to plasmin. It is available as a sterile, friable solid or white powder. It is water soluble and shows maximum activity at pH 7. The solution of higher concentration is stable for 6 hours at 4 degrees centigrade. Dilute solutions are unstable.

English: 3d structure of streptokinase C+D (yellow+green) complexed with plasmin (blue) after PDB 1BML. Ref.: X.Wang et al. (1998). Crystal structure of the catalytic domain of human plasmin complexed with streptokinase.. Science, 281, 1662-1665. PMID 9733510 10.1126/science.281.5383.1662 (Photo credit: Wikipedia)

Medicinal Uses of Streptokinase:

Structure of the catalytic domain of human plasmin complexed with streptokinase. (Photo credit: Wikipedia)

It is used in the treatment of thromboembolic disorders for the lysis of pulmonary emboli, arterial thrombus, deep vein thrombus and acute coronary artery thrombosis. Its activity is mainly to activate plasminogen to give a proteolytic enzyme plasmin, whose activity is to degrade fibrin clots, fibrinogen and other plasma proteins.