This fluorescent protein glows on irradiating it with ultraviolet and blue light, according to a study published on May 30, 2019.
Biophysicists from the Moscow Institute of Physics and Technology collaborated with colleagues from France and Germany to engineer this glowing protein. Under high temperature, this protein is very small and stable. According to the researchers, it holds prospects for fluorescence microscopy.
A technique to analyze and study living tissue using induced luminescence is known as fluorescence microscopy. When the proteins are exposed to laser radiation at a particular wavelength, light is emitted by some of the proteins at a different wavelength. Fluorescent proteins are attached to other proteins via genetic engineering to make the latter ones visible to the microscope and observe their behavior in cells. Although these proteins were used for such observations, it had many disadvantages. They were vulnerable to heat, fairly bulky, and only glowed in the presence of oxygen.
Vera Nazarenko, lead author of the paper said, “For one thing, our protein is more thermostable than its analogues: It only denaturates at 68 degrees Celsius. It is also miniature, while most of the currently used fluorescent proteins are rather bulky. On top of that, it can emit light in the absence of oxygen.” Initially, the research team identified the protein with these properties in the cells of a thermophilic bacterium. Furthermore, a DNA sequence was genetically engineered, which reproduced the protein’s fluorescent segment and not the other parts that would make the molecule larger.
The gene that encodes the protein was introduced into the cells of another bacterium, Escherichia coli. By doing this, they could turn it into a factory mass-producing the fluorescent protein with unique properties. This development finds major application in investigating the mechanism behind malignant tumor genesis and development. This can be done by introducing it into the cells. Proteins that were used previously in fluorescence microscopy were bulky and thermally unstable, which had put limitations on the method.