Libsyn Directory

469: Prophage Provides Partial Protection

Release Date: 04/04/2022

BacterioFiles

This episode: A virus partners with a parasitoid wasp to help exploit fruit fly victims! (7.7 MB, 11.2 minutes) Show notes: Microbe of the episode: Actinomadura livida Takeaways Parasitoid wasps have an interesting lifestyle: they inject their eggs into the larvae of other insects, and their young hatch and grow up by consuming the host from the inside. Some of these wasps also inject a virus along with the egg, which supports the wasp offspring by suppressing the host immune system. Most of these parasitoid helper viruses are integrated into the host wasp genome and are translated and...

489: Soil Smell Synthesis Significance

BacterioFiles

This episode: Many organisms produce the smell of earth, geosmin, and many others can sense it–but why? (6.0 MB, 8.7 minutes) Show notes: Microbe of the episode: Takeaways The smell of soil or earth is one of the most recognizable smells, and comes largely from a chemical called geosmin, produced by many different kinds of bacteria. Many animal species are sensitive to geosmin, some attracted by it and others repelled. But it is still not entirely understood what is the evolutionary benefit to the microbes that produce it, or the reason why different animals are...

488: Social Slimes Synchronize Sorties

BacterioFiles

This episode: Slime mold amoebas Fonticula alba have interesting and unique foraging and reproductive behaviors! (7.3 MB, 10.6 minutes) Show notes: Microbe of the episode: Takeaways How did life develop from single-celled organisms acting independently into the complex, multicellular organisms we see and are today? Although it is difficult to look back through time to study how ancient organisms may have developed along this path, it is possible to investigate modern organisms that occupy a zone in between single-celled and multicellular, to see if we can get some hints to our...

487: Probiotic Pulverizes Pathogen Persisters

BacterioFiles

This episode: A probiotic strain of E. coli can target and destroy pathogens that survive a treatment of antibiotics! (8.2 MB, 12 minutes) Show notes: Microbe of the episode: Streptomyces griseoruber Takeaways Antibiotic resistance is becoming more and more of a problem as bacterial pathogens develop resistance to more and more drugs. For some people who develop an infection that is resistant to everything, it's as if they were living back in the days before antibiotics were discovered, when all they could do was pray for survival. New antibiotics are needed, but even more needed...

486: Biohybrid Bacteria Build Biomass

BacterioFiles

This episode: Incorporating light-absorbing molecules into bacterial membranes can allow bacteria to use solar energy to transform nitrogen gas into fertilizer! (6.5 MB, 9.9 minutes) Show notes: Microbe of the episode: Wheat dwarf virus Takeaways Turning nitrogen gas into biologically useful compounds, such as protein or ammonia for fertilizer, is an essential part of the global nitrogen cycle and therefore, for agriculture. Today much fertilizer is produced from nitrogen gas by a chemical process that requires large amounts of energy, contributing to global warming. But certain...

485: Small Cell Sculpts Sticky Snot Sphere

BacterioFiles

This episode: A marine protist predator traps prey microbes in an attractive bubble of mucus, eats what it wants, and lets the rest sink, possibly sequestering significant amounts of carbon! (7.8 MB, 11.4 minutes) Show notes: Microbe of the episode: Bat associated cyclovirus 1 Takeaways The oceans have a lot of unique, unexplored life in them. This is true on a macro level but even more on a microscopic level, with many different kinds of microbes of various groups with fascinating life strategies. And despite being microscopic, with enough of them around, they can affect the whole...

484: Bacteriophages Boost Brains

BacterioFiles

This episode: Certain phages in the gut are linked with increases in performance on some cognitive tests! (7.5 MB, 10.9 minutes) Show notes: Microbe of the episode: Streptomyces bikiniensis Takeaways Our gut microbiota includes a large number of viruses, mostly bacteriophages. These fall into two groups, the lytic kind that infects and reproduces itself immediately in a host, and the lysogenic kind that can integrate its genome into the host bacterial genome and remain dormant for long periods. In this study, a higher proportion of lysogenic phages was correlated with increased...

483: Recycling Resources Raises Robustness

BacterioFiles

This episode: Adding tags to proteins to increase their degradation can help engineered bacteria grow and survive better under various conditions! (7.3 MB, 10.4 minutes) Show notes: Microbe of the episode: Lactococcus virus sk1 Takeaways Engineering bacteria with new genetic pathways allows us to use them in many new and promising applications. Some of these are industrial fermentations, growing large quantities of bacteria to use as catalysts for production of chemicals of interest, such as biofuels. But in other cases, engineered microbes can be most useful in less controlled...

482: Colony Concentric Clock Construction

BacterioFiles

This episode: Single-celled bacteria can act independently to create patterns and structure in their biofilm communities! (9.6 MB, 14.0 minutes) Show notes: Microbe of the episode: Dictyostelium discoideum Skipper virus Takeaways Large multicellular organisms like us have interesting mechanisms for using one set of genetic instructions present in all cells to form a large, complex community of many different types of cells with different structures and functions, all working together. Single-celled microbes do not have the same requirements for genetic or structural complexity, but...

481: Hijacker-Host Sequence Swap

BacterioFiles

This episode: Gene transfers between viruses and eukaryotes have happened many times throughout evolutionary history! (7.5 MB, 10.9 minutes) Show notes: Microbe of the episode: Mycoplasma subdolum Takeaways As we’ve all seen recently, viruses can cause a lot of trouble. Their biology requires them to be parasites inside the cells of their hosts, and they can cause devastating disease, so it’s hard to think of them as having played important roles in the development of life on Earth, including our own evolution. However, this study found thousands of apparent historical...

More Episodes

This episode: A virus lurking in a bacterial genome protects its host population from infection with other phages, by killing off infected cells!

Download Episode (7.6 MB, 11.0 minutes)

Show notes:
Microbe of the episode: Olive latent ringspot virus

Takeaways

Many bacteriophages just go in and gobble up all their host's resources to make a bunch of new viruses right away. Others play a longer game, splicing into and lurking in the host's genome across multiple generations until conditions are right to multiply more rapidly. It is beneficial to these latter kind when their host is resistant to the fast-killing variety, but how can bacteria be resistant to some phages but not others?

In this study, one prophage (the phage genome integrated into the bacterial genome) carries a gene that does this in an interesting way. It prevents invading phages from replicating and kills the host cell so the infection can't spread, protecting the population (and all the other cells containing the prophage). It also contains an immunity element that allows the prophage to replicate itself without interference.

Journal Paper:
Owen SV, Wenner N, Dulberger CL, Rodwell EV, Bowers-Barnard A, Quinones-Olvera N, Rigden DJ, Rubin EJ, Garner EC, Baym M, Hinton JCD. 2021. Prophages encode phage-defense systems with cognate self-immunity. Cell Host Microbe 29:1620-1633.e8.

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