A Sustainable Optimized Native Lysostaphin Production and Immunopurification Approach for fighting the Problematic Resistant Super Bug Staphylococcus aureus

Abstract

Purpose: Antibiotics, the greatest twentieth century weapon, are faced with a repertoire of resistant microorganisms that lowers their control over life-threatening infections. Hence, mining different natural products for antimicrobial activity has been an attractive approach to combat problematic microorganisms such as the super bug, Staphylococcus aureus. Herein, we propose an optimized production and immunopurification approach for the production of the native staphylococcal cell-wall degrading enzyme “lysostaphin (LST)”. We are presenting this approach as a sustainable platform that would further help circumvent the antibiotic resistance global issue. Methods & Materials: Native LST production from S. simulans cultures was optimized using full factorial design, evaluating the influence of four independent factors (temperature, agitation, media:air ratio, and growth time) against the dependent variable of LST yield measured in unit activity (U)/mg dry weight. The activity of the optimized native LST (N-LST) was tested against a collection of clinical methicillin-resistant S. aureus (MRSA) isolates. Recombinant LST, produced locally at our laboratory, was then used as an immunogen for polyclonal antibodies production in BALB/C mice. Finally, the produced anti-LST IgGs were purified and assessed using enzyme-linked immunosorbent assay (ELISA) and then attached to CNBR-activated sepharose beads to be used for N-LST purification. Results: N-LST optimized production yielded up to 5.6 U/mg dry weight of the native enzyme which is significantly more (153%) than the previously reported yield. The enzyme was also found to be active against clinical MRSA isolates. The immunoaffinity purification of the N-LST was successful and yielded highly active enzyme. Conclusion: The current work identified conditions for N-LST production that yielded a highly active product, surpassing the reported methods. We also offer a sustainable purification platform incase higher grade of the enzyme was required. The current study serves the ongoing efforts to combat the surge in antimicrobial resistance and establishes a good start for the adoption of N-LST production systems to satisfy the research needs in developing countries.