Safer GMOs possible with spread-resistant bacteria

Chuck Bednar for – Your Universe Online
Two teams of US scientists are currently working on a way to produce “safer” genetically modified organisms (GMOs) that would be unable to spread in the wild, finding a potential solution to a primary concern to critics of genetic engineering research.
According to BBC News, the researchers have altered the genetic code of bacteria so that they can only use synthetic chemicals to grow. If they escaped into nature, they would simply die out, ideally alleviating some of the fears over GMOs and opening the door for their increased use in the fields of agriculture, medicine, and environmental clean-up.
As explained in the journal Nature, the bacteria relies upon an amino acid (one of the building blocks of protein) that does not occur in nature. While the microbes can thrive in the lab as long as they have access to the unnatural amino acid, none survived an experiment in which the artificial supplement was withheld.
Genetically engineered micro-organisms are currently used in the US, Europe, and China in order to produce drugs or fuels under contained industrial conditions, the BBC said. However, scientists are looking to develop internal fail-safe measures to help keep them from spreading if used in real-world conditions.
Re-writing the genetic code
“What we’ve done is engineered organisms so that they require synthetic amino acids for survival or for life,” Yale University professor Farren J. Isaacs, who led one of the two studies, told BBC News. “What we’re seeing here is an important proof of concept that re-coding genomes and engineering dependence on synthetic amino acids is technically feasible in not just E coli but other micro-organisms and multicellular organisms such as plants.”
“Our strains, to the extent that we can test them, won’t escape,” added Daniel J. Mandell, a synthetic biologist at Harvard. The new bacteria is also unable to exchange their DNA with the natural versions of the same bacteria, since they no longer speak each other’s genetic language.
The new studies are a “milestone” in synthetic biology and an important step forward to such containment procedures, the researchers said. The work will help address public concerns over the use of GMOs and protecting natural ecosystems by making it impossible for these microbes to spread or to genetically interact with their naturally occurring counterparts.
Nature reported that the new technique originated in the laboratory of Harvard geneticist George Church.
“Church and Isaacs have independently made this engineered microbe reliant on unnatural amino acids,” the journal said. “The Isaacs team used genomic sequencing to identify sites in essential bacterial proteins where the microbes could incorporate synthetic amino acids without affecting overall function, whereas Church’s group started with the protein structures and added elements to help integrate and accommodate the artificial amino acids.”
Church called the breakthrough “the culmination of a decade of work,” while Isaacs said that they hope to re-write the genetic code of other types of organisms in the near future.
Follow redOrbit on Twitter, Facebook, href=””>Instagram and href=”” target=”_blank”>Pinterest a>.