Researchers at the Royal Veterinary College (RVC) have developed a system that eliminates the need for antibiotics and resistance genes in the engineering of industrial and medical products. The method involves safer, less costly alternatives and is well suited for industrial production of many biofuels and biopharmaceuticals. This research has been published in the online access journal BMC Biotechnology.
Genetic engineering underpins much of biotechnology, and antibiotic selection of engineered strains is a key tool. Unfortunately, antibiotic selection methods risk spreading resistance traits, particularly as biotechnology products move into the environment and clinic. There have been alternatives, but none are satisfactory for wide application.
Gene targeting is the insertion of DNA into specific sites or genes within the genome of selected cells in order to alter gene expression for a particular purpose.
While working on gene targeting in bacteria, RVC researchers discovered that a well-known interaction between a cell membrane synthesis gene and the biocide triclosan could be exploited for strain selection. Surprisingly, triclosan selection performs better than conventional antibiotic selection.
“We think this simple technology is well suited for industrial scale fermentations that produce a range of valuable products, including bio-fuels and bio-pharmaceuticals,” said Dr Liam Good, at the Royal Veterinary College and lead researcher on the project. “More importantly, the new system is relatively safe and inexpensive, because the gene is native in all bacteria and triclosan is approved for use in many household applications.”
The research was carried out with Dr Shan Goh of the Department of Cell and Molecular Biology, Karolinska Institute, Stockholm.