CONICET | Buscador de Institutos y Recursos Humanos

Introduction and Objectives: The development of mycobacteriophages containing a fluorescent reporter gene was described as a simple means of revealing the metabolic state of M. tuberculosis cells, and therefore their response to antibiotics. Nowadays, there is a need for new and efficient antitubercular therapeutics that shorten the time of treatment and frequency of administration, less toxic and that require less surveillance of the patient. Our aim is to develop a simple and rapid whole-cell high-throughput screening method for anti-TB drugs using a new generation of Fluoromycobacteriophages. Methodology: We developed a mCherrybombɸ with higher sensitivity and a shorter time to detection of signal compared to the first generation of Fluoromycobacteriophages. Using a fluorimeter, DST (drug susceptibility testing) of M. tuberculosis can be done from pure culture in a convenient multiwell format in 6 or 30 hs (if pre-incubation with the drug is needed). Infection is done in the presence of increasing concentrations of drugs and appearance of fluorescence is monitored as a function of time. The concentration that completely inhibits fluorescence is reported as the minimal inhibitory concentration (MIC) for that drug. We found a good correlation between the values obtained with this technique and the proportion method use as gold standard for TB. Conclusion: We had optimized the conditions to detect infection with Fluoromycobacteriophages using a fluorimeter in a multiwell format. The implementation of this standardized methodology will contribute to the development of a rapid, easy and high sensitive screening of drugs.