Fibrinolytic enzymes belong to the class of proteases that catalyse the breakdown of fibrin clot. Formation of fibrin clot along with the aggregation of platelets result in a hemostatic plug at the site of injury. These fibrinolytic agents are often administered for the treatment of myocardial infarction, strokes, respiratory failure.  The aim of the current research was to examine the effect of sea water and nitrogen sources on the fibrinolytic enzyme activity. Further, an effort was made to purify the enzyme, which was then assayed for fibrinolytic and fibrinogenolytic activities.  Incorporation of sea water in the medium lead to a marginal increase in the enzyme production. Whereas an increase in the NH4Cl concentration resulted in an increased production of enzyme. A combination of 12% (w/v) yeast extract and 4% (w/v) NH4Cl, 1.25% (w/v) soya peptone and 0.075% (w/v) CaCO3 resulted in a 4.1 fold increase in the total enzyme activity of 657 U/mL. These results indicate the remarkably high nitrogen demand of the organism Serratia marcescens subsp. sakuensis. Purification of fibrinolytic enzyme was accomplished by passing through a Sephadex G-100 column, which resulted in a specific enzyme activity of 250 U/mg with a 5.1-fold purity and 6.25% recovery. Additionally, the fibrinogenolytic activity of the purified enzyme was found to be 4.34 U/mg. The fibrinolytic to fibrinogenolytic ratio was found to be 35:1. This data connotes the specificity of the enzyme towards the substrates fibrin and fibrinogen, with the former being preferred.

Keywords: Fibrinolytic; Fibrinogenolytic; Marine; Purification.