"Isaacs and his colleagues systematically replaced one three-letter sequence in the genome of Escherichia coli with another.
Three-letter genetic sequences are known as codons, and they can either code for an amino acid – the building blocks of proteins – or act as stop signals. A cell's internal machinery reads copies of the genome, and as it goes along it links the corresponding amino acids together into protein strings until it reaches a stop codon.
The researchers sifted through the E. coli genome and identified all 314 TAG stop codons. They then designed fragments of single-stranded DNA that, with the assistance of viral enzymes, would replace the TAG stop codons with TAA, another stop codon.
Isaacs submerged a billion E. coli cells in pools of water brimming with the bits of DNA and viral enzymes, and zapped the mixture with electricity, opening pores in the bacteria's cell membranes for the DNA to pass through. The process is known as multiplex automated genome engineering, or MAGE."
Read Further:
http://www.newscientist.com/article/dn20694-e-colis-genetic-code-has-been-rewritten.html
No comments:
Post a Comment