Genetically modified fungi can produce pharmaceuticals from chitin. (Photo: TU Vienna, CC, Hans Hillewaert)
Scientists use crab shells to produce pharmaceuticals
Thursday, February 16, 2012, 00:50 (GMT + 9)
Scientists at the Vienna University of Technology have introduced bacterial genes into a fungus so it can produce chemicals useful to the pharmaceutical industry.
The fungus in question is Trichoderma and it uses chitin, a raw material which makes up the shells of crustaceans, including crabs, that is generally abundant in nature.
Viral infections are usually treated with antiviral drugs, which are often made from N-Acetylneuraminic acid (NANA), a substance fifty times more valuable than gold sold for around EUR 2,000 per g. NANA can be obtained from natural sources or synthesized.
|Biochemical Labs of the Institute for Chemical Engineering. (Photo: TU Wien)
Biotechnologist Astrid Mach-Aigner led a research team at Vienna UT that has discovered a new and environmentally friendly way to produce NANA.
The team realized that it could use the university's accumulated knowhow about the genetics of the fungus Trichoderma –- which is found in soil, meadows and trees -- to make progress.
"We knew that Trichoderma can degrade chitin -– that's what the fungus naturally does in soil", said Mach-Aigner.
The researchers decided that Trichoderma was therefore a viable candidate for the project.
For the fungus to produce NANA, the team injected bacterial genes into the fungus's genome.
"Usually, Trichoderma breaks down chitin to monomer amino sugars", noted Mach-Aigner.
The scientists were able to make possible two extra reaction steps as a result of the genes and allow for the production of the desired pharmaceutical, N-Acetylneuraminic acid.
That the scientists can use chitin for this purpose is very convenient because chitin is the second-most plentiful biopolymer on earth, available in the carapaces of crustaceans, in the shells of insects, snails and cephalopods and in the cell walls of fungi. As it is estimated that in the sea alone 10 billion tonnes of chitin are created every year, the substance is a tremendously sustainable resource for chemical synthesis.
The newly developed Trichoderma line can now be made in bioreactors and produces the acid NANA from chitin. The university has patented the process, which will be employed for the cheap and eco-friendly production of pharmaceuticals on an industrial scale in the near future.
By Natalia Real