New biological treatment targeting Mycobacterium tuberculosis in contaminated wastewater using lysing enzymes coupled to magnetic nanoparticles

Abstract

Wastewater from hospitals and facilities that receive patients infected with contagious microorganisms has dense concentrations of these pathogens, which may represent a threat to public health. Thus, proper wastewater treatment to remove these contaminants before discharging to the sewage system has been a great concern to the society. Aside from chemical and physical treatment, biological alternatives have been more widely studied and implemented for wastewater processing to avoid unwanted effects and to lower the costs. This study aimed to use lysing enzymes coupled to magnetic amino nanoparticles functionalized with specific antibodies (NP-NH2-antibody) to treat wastewater contaminated with targeted contagious pathogens, initially with Mycobacterium tuberculosis, a highly persistent bacterium. The generated complexes captured Mycobacterium bovis in Bacillus Calmette-Guérin (BCG; tuberculosis vaccine), which was subsequently lysed by lysozyme and lipase. The result showed that single complexes (functionalized with either enzyme or antibody) worked more efficiently than dual complexes (coupled to both proteins) and the complexes could be stored refrigerated stably for at least two months. The preliminary assessment of this method in treating wastewater model samples spiked with BCG vaccine showed evidence for the bacteria being captured and eliminated. Further optimization is necessary to implement these complexes in treating pathogen-contaminated wastewater.