CRISPR-Cas9 Mediated Knockout of Gene for Overexpression of Streptokinase in .

Streptokinase is an enzyme that can break down the blood clots in some cases of myocardial infarction (heart attack), pulmonary embolism, and arterial thromboembolism. Demand for streptokinase is higher globally than production due to increased incidences of various heart conditions. The main source of streptokinase is various strains of . Expression of streptokinase in native strain is limited due to the gene-mediated post-translational modification of streptolysin, an inhibitor of streptokinase expression through the degradation of FasX small RNA (through CoV/RS), which stabilizes streptokinase mRNA. In order to improve the stability of mRNA and increase the expression of streptokinase, which is inhibited by SagA, we used CRISPR-Cas9 to successfully knockout the gene and observed a 13.58-fold increased expression of streptokinase at the transcript level and 1.48-fold higher expression at the protein level in the mutant strain compared to wild type. We have demonstrated the successful gene knockout of using CRISPR-Cas9 in where an engineered strain can be further used for overexpression of streptokinase for therapeutic applications.