Targeting mono- and dual-species biofilms of Staphylococcus aureus and Pseudomonas aeruginosa by the recombinant anticoagulant enzyme PAPC from micromycete Aspergillus ochraceus.

Abstract

Microbial biofilms have recently emerged as a critical target for treating bacterial infections due to their crucial role in developing antibiotic resistance. The wide-spectrum activity of proteolytic enzymes makes them particularly suitable for disrupting biofilms formed by diverse bacterial species, including dual-species biofilms. In this study, we propose the Protease-Activator of Protein C (PAPC) of human blood plasma, an enzyme produced by the micromycete Aspergillus ochraceus, as a novel tool to degrade the protein scaffold of mono- or dual-species biofilms formed by Staphylococcus aureus and Pseudomonas aeruginosa. The recombinant PAPC was successfully refolded after expression in E. coli BL21 (DE3) and demonstrated activity 100-fold higher compared to the native enzyme purified from the A. ochraceus culture liquid. The enzyme significantly destroyed mono- and dual-species biofilms formed by S. aureus and P. aeruginosa. In addition, PAPC significantly enhanced the antimicrobial treatment efficacy in both mono- and dual-species biofilms: in the presence of PAPC at 100 μg/ml, the effective concentration of the ciprofloxacin and ceftriaxone was reduced at least four-fold. Thus, the enzyme represents a reasonable solution to the complications resulting from biofilm formation and antibiotic resistance, especially wound and medical devices infections.