“Zombie” cells in the laboratory, science manages to bring dead cells back to life

The process is based on the inactivation of the genome of the recipient cell, usually Mycoplasma capricolum, through the use of mitomycin C, a drug that damages DNA, preventing cell replication. This step is crucial to eliminate the risk of “false positives”, i.e. cells that survive by incorporating only fragments of the new DNA via homologous recombination instead of the entire genome. Once the cell is functionally dead, the synthetic Mycoplasma mycoides genome is inserted. As explained by Zumra Peksaglam Seidel, synthetic biologist at the JCVI“The cell is destined to die, but we give it life». The result is a fraction of cells that replicate again following exclusively the instructions of the new genetic code.

This methodology overcomes limitations observed over the past 15 years, during which genomic transplants were limited to closely related species within the same bacterial class. The long-term goal is to extend this practice to organisms more common in the laboratory, such as Escherichia coli. Olivier Borkowski, INRAE ​​researcher, said: “This work represents a significant step forward for genome engineering in synthetic biology. If the technique becomes routine, it would allow testing of entirely computer-engineered genomes to transform bacteria into biofactories capable of producing sustainable fuels or complex pharmaceutical molecules with unprecedented efficiency.”