Today’s arsenal of antibiotics is ineffective against some emerging strains of antibiotic-resistant pathogens. Novel inhibitors of bacterial growth therefore need to be found. One way is looking into the viruses that infect bacteria.
Key to the new initiative is the concept of fighting bacteria from within, rather than using an external chemical to batter through the bacterial cell wall. the basis of the new weapon is viral. In order to select an appropriate viral protein, researchers undertook a comprehensive screening exercise in order to identify proteins in viruses that are known to infect bacteria (bacteriophages). Bacteriophages occur abundantly in the biosphere, with different virions, genomes and lifestyles. The review was so comprehensive that it took almost three years to complete.
The screening was achieved through the use of high-throughput DNA sequencing. This is the process of determining the precise order of nucleotides within a DNA molecule. By using this advanced genetic method, the scientists identified mutations in bacterial genes that resisted the toxicity of growth inhibitors produced by bacterial viruses. Through this, a new, tiny protein was found. The protein is termed “growth inhibitor gene product (Gp) 0.6”.
Later testing found that the protein specifically targets and inhibits the activity of a protein essential to bacterial cells. The bacterial protein affected has the function of holding the microbe’s cell wall together. Without this protein functioning correctly, the cell bursts open from within and the bacterium dies.
For the next wave of research, the Israeli science group are looking further at bacterial viruses with the aim of finding compounds that facilitate improved treatment of antibiotic-resistant bacteria.
The research was carried out at Tel Aviv University. The findings have been published in the journal Proceedings of the National Academy of Sciences, in a research paper titled “Revealing bacterial targets of growth inhibitors encoded by bacteriophage T7.”