Molecular identification and optimization of media components for enhanced production of staphylokinase produced by Staphylococcus aureus SAK42 from bovine milk

3 Biotech. 2025 Jul;15(7):230. doi: 10.1007/s13205-025-04398-z. Epub 2025 Jun 30.

Abstract

Cardiovascular diseases (CVDs) are the leading cause of global death due to localized thrombosis in the circulatory system. Microbial fibrinolytic enzymes are being explored as a new remedial seeker for CVDs due to their affinity, specificity, catalytic ability, and stability, and are drawing a lot of attention as thrombolytic medicines in the contemporary context. The present study is designed for the identification of most potent staphylokinase-producing Staphylococcus aureus strain from cow milk with the highest production and low immunogenicity risk. Among 120 isolates, SAK42 was found to have the highest potential for staphylokinase production and identified as Staphylococcus aureus (GenBank: OQ891761.1) based on 16S rRNA sequencing analysis. SAK42 was further explored for the enhanced staphylokinase production, and its activity using One Factor at a Time (OFAT) method. It displayed the highest staphylokinase activity at optimal parameters of pH 8.0, a temperature of 35 °C, and 24 h of incubation. Sucrose, yeast extract, and NaCl, were identified as best nutrients for maximal enzyme secretion by S. aureus SAK42. A remarkable threefold increase in staphylokinase production was achieved from 1.49 U/mL ± 0. 2 to 5.58 ± 0.1 U/mL on TSB medium (p < 0.05). An impressive 88% lysis of the clot was achieved at dosage of 5.58 U/mL by in vitro clot lysis method. All these results inferred that the SAK42 has significant potential for staphylokinase production and could be efficiently utilized in future for the cost-effective production of thrombolytic drugs.

Supplementary information: The online version contains supplementary material available at 10.1007/s13205-025-04398-z.

Keywords: Cardiovascular disease; Low immunogenicity; Microbial therapeutic agent; Optimization; Staphylokinase; Thrombolytic potential.