Which bacterium was used to create the first cell controlled by a chemically synthesized genome?

Mycoplasma mycoides was used to create the first cell controlled by a chemically synthesized genome.

In 2010, researchers at the J. Craig Venter Institute reported a landmark experiment involving M. mycoides. They chemically synthesized a copy of its genome, added identifying DNA sequences, and transplanted the genome into a related Mycoplasma capricolum cell whose original DNA had been removed or inactivated.

The recipient cell was then controlled by the synthetic M. mycoides genome and reproduced as M. mycoides. The researchers called the resulting organism a “synthetic cell” because its genome was synthetic, even though the surrounding cellular machinery and cell membrane were derived from a natural cell.

This experiment did not create life entirely from nonliving chemicals. That distinction is important: the achievement was genome synthesis and transplantation into an existing cell. Mycoplasma was chosen partly because its genome is comparatively small and its cells lack a rigid cell wall.