Researchers have developed a way to use baker’s yeast in a new and easy detection mechanism for the common person to detect most fungal infections.
Fungi are a kingdom of microorganisms what we know of in general terms as yeast, molds, and mushrooms. Separate from bacteria and viruses, they can also cause infections within the human body. Some of these well-known fungi causing infections are candida (diaper rash, vaginal infections, and mouth ulcers) and tinea (athlete’s foot, jock itch, and ringworm). They can cause serious internal infections and if not treated appropriately they can even lead to death. Fungi can cause damage to crops, with serious financial implications for farmers. However, as deadly some fungi can be, there are also some healthy fungi that are used frequently in cooking. An example of this would be the baker’s yeast that is used to make bread and a variety of pastries. Detecting fungal infections is not difficult to well-stocked laboratories in western countries. However, since the tests require sophisticated lab equipment and refrigeration, testing for fungal infections in developing countries is significantly more challenging.
Researchers at Columbia University have discovered a cheap and accessible method that can be used to detect fungus in humans and plants. A research team led by Virginia Cornish aimed to create a test that had long shelf life and no refrigeration required. The results were reported in Science. Current tests are dependent on the presence of antibodies. Antibodies are particles that attach themselves to particular fungi in order to identify them in a sample.
For the experiment, Virginia used commonly found fungi – baker’s yeast, or Saccharomyces cerevisiae. Baker’s yeast has characteristics found on most fungi, including mating receptors and the potential to detect pheromones. Virginia then took a mating receptor from a lethal infection-causing fungi, candida, and attached it to the genes of the baker’s yeast. They also added other genes to the baker’s yeast that would help it to produce a red colour if it came in contact with the Candida fungi. Results of the interaction between the baker yeast and candida were available in about three hours after the test was performed. They then created ten different variations to detect other kinds of fungi. In doing so, they were able to detect the presence of harmful fungi, Magnaportheoryzae and Fusarium graminearum.
The engineering of a usable device to test for fungi in urine, blood, and other fluid samples proved to be quite easy. The researchers covered a paper dipstick with the modified baker’s yeast. This yeast covered dipstick was then dipped into the urine, blood, or fluid sample and results are available in less than three hours. This method proves to be an exciting and easy way that labs and even day to day people can grow their own investigating systems for detecting a fungi infection. Moreover, the yeast covered paper dipstick was still functional after being stored at room temperature for about 38 weeks, making it easily one of the most manageable diagnostic tests available.
This groundbreaking research has important implications for health and agriculture in developing countries. The benefits of this research are numerable, but the most noteworthy aspect lies in the fact that the fungal infections contaminating the household, human body or plants can be easily detected by everyone since the detecting yeast is already part of a household kitchen. While some aspects of the test need to be worked on to improve sensitivity and specificity to the detection of most fungal infections, it paves the path for the development of easier methods to detect bacterial and viral diseases.
Written by Dr. Apollina Sharma, MBBS, GradDip EXMD
Reference: Science | AAAS. (2017). How scientists are combatting deadly fungus—with baker’s yeast. [online] Available at: http://www.sciencemag.org/news/2017/06/how-scientists-are-combatting-deadly-fungus-baker-s-yeast [Accessed 13 July 2017].