Aminoglycoside Antibiotics Inhibit Mycobacteriophage Infection

Abstract

Antibiotic resistance is becoming the biggest threat to global health. At the same time, phage therapy is witnessing a return of interest. The therapeutic use of bacteriophages that infect and kill bacteria is a suitable strategy to combat antibiotic resistance. Furthermore, bacteriophages are increasingly used in combination with standard antibiotics against drug-resistant pathogens. Interestingly, we found that the engineered mycobacteriophage phAE159 and natural phage D29 cannot infect the Mycobacterium tuberculosis in the presence of kanamycin, hygromycin or streptomycin, but the phage infection was not affected in the presence of spectinomycin. Based on a series of studies and structural analysis of the above four aminoglycoside antibiotics, it could be speculated that the amino sugar group of aminoglycoside might selectively inhibit mycobacteriophage DNA replication. Our discovery that broad-spectrum antibiotics inhibit phage infection is of great value. This study will provide guidance for people to combine phage and antibiotics to treat M. tuberculosis.

Keywords: aminoglycosides; antibiotic resistance; mycobacteriophage; phage therapy; tuberculosis.

Figure 1

Aminoglycoside antibiotics inhibit the DNA replication of mycobacteriophages. (a) The replication of the two mycobacteriophages phAE159 and D29 were inhibited by kanamycin on the lawns of M. smegmatis mc²155. (b) Kanamycin did not affect the infection of Escherichia coli phages T7 and λ. (c) Hygromycin was able to inhibit the infection of mycobacteriophages phAE159 and D29. (d) Kanamycin inhibited the formation of plaques by electrotransformation of phAE159 vector. (e) Pre-incubation with kanamycin did not affect the infection of mycobacteriophage phAE159. (f) M. smegmatis mc²155 harboring the recombinant plasmid tolerated streptomycin and spectinomycin well. (g) The propagation of mycobacteriophage D29 was significantly inhibited in the presence of streptomycin but had no effect in the presence of spectinomycin. (h) TEM analysis of the adsorption capacity of mycobacteriophage in the presence of streptomycin. (i) Quantitative PCR analysis of phage DNA proliferation during the infection process. (j) Aminoglycosides were speculated to be able to block the DNA replication during the life cycle of phage (adapted from Figure 3a in [21]).