451 - Phototrophs Fancy Floating Feasts

Prasinophyte algae
By Bock et al. 2021, ISME J
CC BY 4.0

This episode: Despite being photosynthetic, some kinds of algae engage in predatory behavior, hunting and consuming live bacteria!

Thanks to Nicholas Bock for his contribution!

Download Episode (4.9 MB, 7.1 minutes)

Show notes:
Microbe of the episode: Paramecium bursaria Chlorella virus 1

News item

Takeaways

Although most of them are microscopic, algae perform a significant portion of the photosynthesis on the planet, because there are so many of them. But even though photosynthesis seems like a reliable way of acquiring energy, there are conditions under which even algae benefit from gathering energy and nutrients from other organisms. This is called phagomixotrophy, when algae hunt and consume bacteria.

In this study, scientists developed fluorescence methods for detecting and studying this predation in a group of algal phytoplankton that's not well-studied, prasinophytes. They found that all five species they looked at engaged in bacterivory under nutrient-depleted conditions, and that they preferred live bacteria to killed ones.

Journal Paper:
Bock NA, Charvet S, Burns J, Gyaltshen Y, Rozenberg A, Duhamel S, Kim E. 2021. Experimental identification and in silico prediction of bacterivory in green algae. ISME J.

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

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450 - Subterranean Spotlights Support Cyanobacteria

Carlsbad Caverns
By Eric Guinther, Marshman
CC BY-SA 3.0

This episode: Lighting in caves open to tourists supports the growth of unwanted photosynthetic bacteria!

Thanks to Zoë Havlena for her contribution!

Download Episode (6.6 MB, 9.5 minutes)

Show notes:
Microbe of the episode: Dill cryptic virus 2

Takeaways

Caves can contain amazing beauty, intricate geological formations formed by minerals, water, and time. Some, such as Carlsbad Caverns in New Mexico, have been fitted with instruments to allow tourists to pass through and see the wonders within; definitely a worthwhile experience.

Caves also have their own natural microbiota that can live within them, in the dark, somewhat cold, and nutrient-poor conditions. But with the lighting installed to allow tourism, photosynthetic microbes have been able to take hold in the communities of these show caves. These microbes can outcompete the natural microbes, and can cause discoloration and unwanted growths on cave formations. They are difficult to remove without much effort and the risk of damaging the cave formations themselves. 

This study looked at the effects of the color of lighting in the caves, as well as other factors, on the growth of these so-called "lampenflora." It supports new efforts and methods to control the issue.

Journal Paper:
Havlena Z, Kieft TL, Veni G, Horrocks RD, Jones DS. 2021. Lighting Effects on the Development and Diversity of Photosynthetic Biofilm Communities in Carlsbad Cavern, New Mexico. Appl Environ Microbiol 87.

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.