Expression of lumbrokinase protein genes in Escherichia coli

In this study, we present a novel method for the heterologous expression of lumbrokinase proteins in Escherichia coli, aimed at overcoming the limitations of traditional extraction and purification processes. By lowering the expression temperature to 16 °C, we successfully reduced the formation of inclusion bodies and expressed three lumbrokinase proteins-A0A0P0YK20, A8ILN1, and Q8I6N3-demonstrating fibrinolytic activity with enzyme activities of 7040 U/mL, 46,772.6 U/mL, and 21,800 U/mL, respectively. These activities surpass those reported in other literature. This approach eliminates the lengthy growth cycles and complex extraction methods associated with earthworm-derived lumbrokinase, significantly improving production yield. Furthermore, the individual lumbrokinase proteins exhibited higher thrombolytic activity compared to their combined forms, highlighting the potential for optimized therapeutic applications. Despite these advances, challenges remain, including the persistence of contaminating E. coli proteins in the purified samples, necessitating further optimization of the purification protocol. Our findings provide a promising strategy for scalable and standardized production of lumbrokinase, paving the way for its broader clinical use.