454 - Hitchhiking Horticultural Helpers

Bacteria carrying spores
By Muok et al. 2021
ISME J, CC BY 4.0

This episode: Spores of some bacteria latch onto the tails of other bacteria and ride along as they move around in the soil!

Download Episode (5.5 MB, 8.0 minutes)

Show notes:
Microbe of the episode: Bohle iridovirus

News item

Takeaways

The soil is a complex environment, and microbes that live in soil need complex lifestyles to thrive. There are many examples of cooperation, competition, and other adaptations to highly varied situations.

In this study, bacteria that grow like filamentous fungi don't have the mechanisms to move autonomously, but their spores can hitch rides on other kinds of bacteria that swarm through the soil using their propeller-like tails called flagella to push themselves toward the plant roots they prefer to grow near.

Journal Paper:
Muok AR, Claessen D, Briegel A. 2021. Microbial hitchhiking: how Streptomyces spores are transported by motile soil bacteria. ISME J.

Other interesting stories:

• "How microbes in permafrost could trigger a massive carbon bomb"

Post questions or comments here or email to bacteriofiles@gmail.com. Thanks for listening!

Subscribe: Apple Podcasts, Google Podcasts, Android, or RSS. Support the show at Patreon, or check out the show at Twitter or Facebook.

453 - Phenazine Faciliates Phosphorus Feeding

Pseudomonas aeruginosa
By Y_tambe, CC BY-SA 3.0

This episode: Some bacteria produce antibiotics that can also help them gather more nutrients!

Download Episode (5.0 MB, 7.3 minutes)

Show notes:
Microbe of the episode: Diadromus pulchellus toursvirus

News item 1

Takeaways

Antibiotics have saved a lot of lives since they were discovered and used to treat many previously untreatable bacterial infections. But bacteria themselves have been making antibiotics much longer than we have, to help compete in their environment. However, sometimes these compounds are not produced in large enough concentrations to act as antibiotics, killing or inhibiting rival bacteria. Why waste energy on this sublethal production? Are there other functions these molecules can perform?

In this study, bacteria produce an antibiotic called phenazine that can damage cell components by redox reactions, transferring electrons. But it can also help liberate the essential nutrient phosphorus from being bound to insoluble particles, allowing the bacteria to grow better even in the absence of competitors.

Journal Paper:
McRose DL, Newman DK. 2021. Redox-active antibiotics enhance phosphorus bioavailability. Science 371:1033–1037.
Other interesting stories:

• Bacterial proteins stuck to tumor cells could be targeted

Post questions or comments here or email to bacteriofiles@gmail.com. Thanks for listening!

Subscribe: Apple Podcasts, Google Podcasts, Android, or RSS. Support the show at Patreon, or check out the show at Twitter or Facebook.

452 - Prokaryotic Partner Powers Protist

Anaerobic ciliate
By Graf et al. 2021
Nature, CC BY 4.0

This episode: Single-celled eukaryotes can thrive without oxygen with the help of bacterial endosymbionts that respire nitrate the way our mitochondria respire oxygen!

Thanks to Jon Graf for his contribution!

Download Episode (12.4 MB, 18.1 minutes)

Show notes:
Microbe of the episode: Brenneria salicis

News item 1 / News item 2

Takeaways

The combination of a bacterium and other microbe into the first eukaryote was a big advance in evolutionary history; it made possible the huge variety of different body shapes and sizes we see today. This is thanks to the bacterial endosymbiont, the mitochondrion, taking on specialized metabolic tasks for the cell.

We already knew about endosymbionts that help with oxygen respiration, with photosynthesis (chloroplasts), and with amino acid synthesis (certain endosymbionts in insects). But bacteria have other metabolic abilities that are very useful in certain conditions; do these bacteria ever team up with other organisms? The answer is yes! In this study, ciliates were discovered at the bottom of a lake in oxygen-free waters. These protists have an bacterial endosymbiont that helps them respire, not oxygen, but nitrate instead, generating more energy than most anaerobic ciliates.

Journal Paper:
Graf JS, Schorn S, Kitzinger K, Ahmerkamp S, Woehle C, Huettel B, Schubert CJ, Kuypers MMM, Milucka J. 2021. Anaerobic endosymbiont generates energy for ciliate host by denitrification. Nature.

Other interesting stories:

• Bacterial cellulose film is very good at separating oil and water

Post questions or comments here or email to bacteriofiles@gmail.com. Thanks for listening!

Subscribe: Apple Podcasts, Google Podcasts, Android, or RSS. Support the show at Patreon, or check out the show at Twitter or Facebook.