synthetic Escherichia coli C321.deltaAsubstrain rEc.y.dC.46 Genome sequencing. synthetic Escherichia coli C321.deltaA

Construction of a series of genomically recoded organisms whose growth is restricted by the expression of essential genes dependent on exogenously supplied synthetic amino acids introduces novel ortho- gonal barriers between these engineered organisms and the environment, thereby creating safer gen- etically modified organisms.