[UncleEntity]

> Synvivia develops biomolecular ON-OFF switches to make synthetic biology safe for use outside of the laboratory.

Yep...then the on-off switch jumps species and the only way to survive is to consume a particular (patent pending) brand of parsnip which can't be grown from seed.

Pretty much the only place I could reasonably be accused of being a luddite is in releasing GM organisms into the wild.

[pazimzadeh]

I definitely agree about the wild. But what about designing gut bacteria that target parasites in your poop? Amongst many other possibilities.

You can use oxygen, temperature, and light-sensitive gene promoters and toxin-antitoxin plasmids to make ON-OFF switches that would hobble bacterial replication in the wild.

It's a tough problem, and my guess is you'd want to use several of these switches together. There's no guarantee that stressed bacteria will 'run' your programs. And you're right that the gene could move horizontally, so you'd have to be very clever with your kill switches, and keep up with evolution.

Apart from the last resort of antibiotics, you can also selectively deplete particular bacteria from your poop using adhesion inhibitors such as mannosides and galactosides (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5654549/ - research from my lab).