Baylor Scientists Shine New Light on Optogenetics Research

The human gut microbiome is full of bacteria, fungi, protozoa, and other unicellular organisms. Evidence suggests that the health of the human gut biome plays a significant role in regulating aging. Researchers have found it challenging to isolate specific microbial species to determine how they influence the gut biome. New breakthroughs from the Baylor College of Medicine may offer a path to identifying specific microorganisms. 

The scientists developed a system that uses light to regulate gene expression in bacteria that reside in the gut. As an analog for a human gut biome, the researchers used the laboratory worm C. elegans. Work by the research team revealed that certain E. coli bacteria would react to green light by producing colonic acid. Colonic acid is protective and increases the lifespan of the C. elegans worm. 

The use of light to initiate gene expressions, called optogenetics, has the potential to be a simple and cost-effective way of modifying genetic material in microorganisms. In the case of the C. elegans experiment, the scientists found that the degree of protection conferred by the green light directly correlated to the intensity of the light source. The brighter the light, the greater the benefit to the work. 

The research team at Baylor has demonstrated a new technique for modifying microorganisms in a living organism’s gut microbiome. As the technology progresses, scientists will search for a way to apply the research to humans. One day, a physician may prescribe highly specific therapies to patients after surveying their gut biome. By directly modifying gene expression, scientists could control bacteria at will, inducing the excretion of protective substances or restricting the release of toxic materials.