In daylight Neonotopanus nambi is a rather inconspicuous brown mushroom. But the surprise is hidden behind the gray facade: at night the fungus glows green. Neonotopanus nambi is one of more than 100 species of fungi that produce light. Aristotle has already documented this phenomenon, called bioluminescence, when he described a glowing, rotting tree threshold. Now scientists have discovered for the first time a biochemical pathway that makes it possible to illuminate bioluminescent fungi. But they went even further: putting three genes necessary for luminescence generation into non-luminous yeast, they created artificially luminescent eukaryotes. Fedor Kondrashov, a professor at the Institute of Science and Technology of Austria (IST Austria), co-authored a study published today in PNASheaded by Ilya Yampolsky at the Institute of Bioorganic Chemistry of the Russian Academy of Sciences in Moscow.
Glowing fireflies and glowing mushrooms on the forest belt are among the few things that can be seen in the dark night darkness in the Brazilian forest. Both behave like lively night lights due to the bioluminescence process, a natural phenomenon by which a substance, called luciferin, is oxidized by the enzyme luciferase to emit light. Bioluminescence is found in many species, from luminous worms to deep-sea fish. However, until now the biochemical pathway that luciferin makes has not been understood in any organism except bacteria. This lack of knowledge prevented attempts by higher organisms, such as animals and plants, to glow. Currently, international cooperation between twelve different institutions under the leadership of Elijah Yampolsky with the participation of Fyodor Kondrashov, Louise Gonzalez Somermeier and his previous member of the group Karen Sargsyan defined how eukaryotes Neonotopanus nambi glowing.
Scientists have discovered key genes responsible for bioluminescence Neonotopanus nambiUsing library screening and genome analysis, the team identified enzymes that contribute to the synthesis of luciferin. They showed that fungal luciferin, the substrate for the bioluminescence reaction, is just two enzymatic steps from a well-known metabolite called caffeic acid, which generates the fungus. Comparing the mushrooms that glow with those who do not, the Kondrashov team also discovered how duplication of genes allowed bioluminescence to develop more than a hundred million years ago. Why did it develop, it is still unclear, Kondrashov says: “Is bioluminescence useful or just a by-product? We don't know yet. There is evidence that the glow attracts insects, which distribute spores. But I don't think that is convincing.
Knowing how the glow of bioluminescent mushrooms glows, the researchers then illuminated non-bioluminescent eukaryotes. Insert the gene encoding luciferase in Neonotopanus nambi along with three other genes whose products form a chain that converts a metabolic acid acid into a reaction substrate, luciferin, into yeast Pichia pastoris led to luminous yeast colonies. “We do not supply a chemical that makes yeast. Instead, we supply the enzymes necessary to convert a metabolic product that is already present in yeast to light, ”explains Kondrashov.
This discovery can be widely used from tissues that report changes in their physiology by lighting up to the creation of luminous animals and plants. “If we think of fantastic scenarios in which luminous plants replace street lights, that's all. This is a breakthrough that could lead to this, "concludes Kondrashov." However, this may take several years until such a street lamp is designed. "
Austrian Institute of Science and Technology, ,