ScienceDaily recently featured a study conducted by researchers from the John Innes Centre who used gene-editing advances to “achieve a tenfold increase in the production of super-bug targeting formicamycin antibiotics.” Their work is promising because, under laboratory conditions, superbugs like MRSA do not develop a resistance to formicamycins.
Streptomyces formicae is a strain of bacteria found in the nests of African ants, which use the antibiotic producing bacteria to defend against pathogens. Half of all known antibiotics discovered within the last 60 years are also derived from metabolites of Streptomyces bacteria. However, S. formicae can only produce small quantities of antibiotics, which has presented a challenge in scaling up purification of the metabolite for further study and clinical trials.
In this study, the team of researchers uncovered the roles of three important gene regulators and combined mutations to maximize antibiotic production. Researchers used CRISPR/Cas9 genome editing to add an extra copy of the formicamycin boosting gene (forGF) and to delete the formicamycin repressor gene (forJ). The result was a new strain of S. formicae bacteria that produces ten times more formicamycin antibiotics and allows for the molecules to grow in liquid culture – something that previously had not been achieved and was a barrier to the clinical research of this compound.
Dr. Rebecca Devine, first author, stated “formicamycins are promising and powerful new antibiotics and we have used gene editing to generate a strain which over-produces these molecules. This will allow us to understand how they work and determine if they have the new potential for clinical development.”
