Scientists alter the genetic code of a living being for the first time

The pathogenic fungus Candida albicans is one of several microorganisms with the unusual ability to manufacture several amino acids (the constituents of proteins) from the same three-letter DNA code (called a codon). This ability breaks one of the rules of the genetic code, according to which each DNA codon codes for just one amino acid. In the latest issue of the journal Proceedings of the National Academies of Science -USA (PNAS), Manuel dos Santos and his team from the University of Aveiro recreated in the laboratory what the fungus Candida albicans can do in nature: alter its genetic code so that from the CUG codon it produces the amino acid leucine instead of serine. This is the first time that the genetic code of a living being has been altered in the laboratory. Surprisingly, the genetically altered fungi revealed a remarkable ability to adapt to different environments, resist antimycotics and induce immune and inflammatory responses in infected mice. This research, funded by FCT and a European project under the 7th Framework Program, helps to understand how the manipulation of the genetic code of fungi and other microorganisms could be used to combat drug resistance and applied in biotechnology and medicine.