Streptomyces

Just like penicillin comes from a mold, some of these drugs also have natural origins.

Tetracyclines are produced by Streptomyces bacteria.

They bind to the 30S ribosomal subunit, which shuts down protein production.

A common example you've probably heard of is doxycycline.

How does that work in practice?

Well, researchers can now identify these silent clusters digitally, clone the specific gene sequences, and splice them into a highly optimized surrogate host like a specialized strain of Streptomyces or E. coli.

Wow.

Or alternatively, they can use CRISPR-based tools to insert genetic promoters right next to the silent cluster in the original organism, artificially forcing the bacteria to turn the genes on and manufacture the compound.

Look at Japan, okay? And this is like, I'll just go off topic there.

Um, Japan has a good soil, right? Streptomyces is in their soil, right? Which is the fermented product, which is the bacteria, fermented product that made ivermectin, right? Their soil is rich.

Is the soil rich in Japan, and is that why they're surviving COVID? Because their foods are getting the right microbes, and therefore they're eating the right microbes, and therefore they're healthier? We have, in America, you know, removed, killed our soils.

How do you replenish that, you know? And then so you're doing-- And this is the problem, and this is the problem we keep doing, right? We keep killing.

[laughs] But they make a deletion mutant of the fungus lacking the beauvericin synthase gene, and those fungi do not cause disease in tomato.

They do not decrease the growth of Streptomyces, uh, in the soil.

Uh, just o- a few more ex- one more experiment here.

So the beauvericin also does other things to the soil.

It, it changes the, the, the community diversity, so it's not just hitting Streptomyces.

And so what else is going on? They, they want to, uh, find out.

They do an experiment which shows that there are consequences of this beauvericin-induced microbiota shifts.

So it's not just Streptomyces, it's, it's other things as well.