@yafuzzball- viruses can replicate, but only by hijacking portions of the cellular machinery of the host cell they have infected. Thus they are not “self-replicating”. The virus phiX174 has a genome of 5,386 nucleotides. They built a 1,077,947 bp genome from scratch.

@blehastic- they made enough changes to their engineered genome that they could perform sensitive PCR-based tests to show no traces of the natural genome was present in cultures of their engineered cells.

@arby186- vectors must be carried by a host. They started from scratch and made the genome OF the host. They built an engineered 1,077,947 basepair genome completely from synthetic oligonucleotides. Their first attempt failed because they made a 1 basepair error. This is only a proof of concept because the engineered bacteria can’t do anything new that the natural bacteria can’t do. But it opens up the possibility of making bacteria that perform certain functions far better than natural bacteria with the modest genome tweaks allowed by conventional technology. Possibilities include bacteria that make molecules that can be used as an antimalarial drug, bacteria that make oil that can be used to fuel an internal combustion engine, bacteria that glow when any TnT residue is present, etc.

And some funny comments: