| Scientists Create First "Stable" Semisynthetic Organism
U.S. scientists on Monday announced the development of the "first" stable semisynthetic organism, an advancement that may have major implications for medicine and even pave the way for the creation of new life forms. "We've made this semisynthetic organism more life-like," senior author Floyd Romesberg, professor of the Scripps Research Institute, said in a statement. All life on Earth is built from four natural bases, called A, T, C and G, but in 2014, Romesberg and colleagues expanded life's genetic code from four letters to six by adding two synthetic bases called X and Y to the DNA of Escherichia coli bacteria. However, the resulting semisynthetic organism grew slowly, and cannot keep the synthetic base pair in their code indefinitely as they divided. In the new study, the researchers optimized a tool called a nucleotide transporter, making it much easier for the semisynthetic organism to grow and divide while holding on to X and Y. The researchers also described in the U.S.