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    399: Conductor Creating Carbon Canvases

    enOctober 14, 2019

    About this Episode

    This episode: Bacteria can aide the production of the useful material graphene, using their ability to add electrons to external surfaces!

    Download Episode (7.7 MB, 11.3 minutes)

    Show notes:
    Microbe of the episode: Brevibacterium frigoritolerans

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    Takeaways
    Advanced materials often take advanced techniques to create, but they offer numerous benefits: increased strength and flexibility, smaller size, more options. One such material is graphene, which is basically a sheet of carbon atoms linked together like chainmail. It is only a single atom thick but is amazingly strong, mostly transparent, and good at conducting heat and electricity.

    The trick is, it's hard to make in large quantities cheaply and easily. Sheets of carbons can be obtained from blocks of graphite, but these sheets are graphene oxide, which lack the desirable properties of graphene. Chemical methods can be used to remove the oxidation, but they are harsh and difficult. Luckily, bacteria are great at microscopic remodeling. In this study, electron-transferring bacteria are able to reduce the graphene oxide to graphene with properties almost as good as are achieved by chemical reduction.

    Journal Paper:
    Lehner BAE, Janssen VAEC, Spiesz EM, Benz D, Brouns SJJ, Meyer AS, van der Zant HSJ. 2019. Creation of Conductive Graphene Materials by Bacterial Reduction Using Shewanella oneidensis. ChemistryOpen 8:888–895.

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    Recent Episodes from BacterioFiles

    489: Soil Smell Synthesis Significance

    489: Soil Smell Synthesis Significance

    This episode: Many organisms produce the smell of earth, geosmin, and many others can sense it–but why?

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    Show notes:
    Microbe of the episode: Acidianus spindle-shaped virus 1

     
     
    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 sensitive to it in different ways.

    In this study, different geosmin-producing bacteria were paired with tiny bacteria-eating roundworms, nematodes, to see how the chemical affected their interactions. Production of geosmin affected the worms' movement, apparently inducing them to avoid colonies of the producing microbes in some cases, though the worms still sometimes fed on the bacteria. Adding geosmin to colonies of different bacteria did not affect the worms' behavior though, so other factors seem to be involved.



    Journal Paper:

    Zaroubi L, Ozugergin I, Mastronardi K, Imfeld A, Law C, Gélinas Y, Piekny A, Findlay BL. 2022. The Ubiquitous Soil Terpene Geosmin Acts as a Warning Chemical. Appl Environ Microbiol 88:e00093-22.

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    488: Social Slimes Synchronize Sorties

    488: Social Slimes Synchronize Sorties

    This episode: Slime mold amoebas Fonticula alba have interesting and unique foraging and reproductive behaviors!

    Download Episode (7.3 MB, 10.6 minutes)

    Show notes:
    Microbe of the episode: Cajanus cajan Panzee virus

     
    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 own development, and also learn about some interesting microbes along the way!

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    Journal Paper:

    Toret C, Picco A, Boiero-Sanders M, Michelot A, Kaksonen M. 2022. The cellular slime mold Fonticula alba forms a dynamic, multicellular collective while feeding on bacteria. Curr Biol 32:1961-1973.e4.

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    487: Probiotic Pulverizes Pathogen Persisters

    487: Probiotic Pulverizes Pathogen Persisters

    This episode: A probiotic strain of E. coli can target and destroy pathogens that survive a treatment of antibiotics!

    Download Episode (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 are new ways of approaching treatment of infections, using innovative approaches and combinations of therapeutics.

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    Journal Paper:
    Hare PJ, Englander HE, Mok WWK. 2022. Probiotic Escherichia coli Nissle 1917 inhibits bacterial persisters that survive fluoroquinolone treatment. J Appl Microbiol 132:4020–4032.

     

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    486: Biohybrid Bacteria Build Biomass

    486: Biohybrid Bacteria Build Biomass

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    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 bacteria can perform the same process using special enzymes much more efficiently.

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    Journal Paper:
    Chen Z, Quek G, Zhu J, Chan SJW, Cox‐Vázquez SJ, Lopez‐Garcia F, Bazan GC. 2023. A Broad Light‐Harvesting Conjugated Oligoelectrolyte Enables Photocatalytic Nitrogen Fixation in a Bacterial Biohybrid. Angew Chem Int Ed 62:e202307101.

     

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    485: Small Cell Sculpts Sticky Snot Sphere

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    Show notes:
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    Journal Paper:
    Larsson ME, Bramucci AR, Collins S, Hallegraeff G, Kahlke T, Raina J-B, Seymour JR, Doblin MA. 2022. Mucospheres produced by a mixotrophic protist impact ocean carbon cycling. Nat Commun 13:1301.

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    Download Episode (7.5 MB, 10.9 minutes)

    Show notes:
    Microbe of the episode: Streptomyces bikiniensis

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    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.

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    Journal Paper:
    Mayneris-Perxachs J, Castells-Nobau A, Arnoriaga-Rodríguez M, Garre-Olmo J, Puig J, Ramos R, Martínez-Hernández F, Burokas A, Coll C, Moreno-Navarrete JM, Zapata-Tona C, Pedraza S, Pérez-Brocal V, Ramió-Torrentà L, Ricart W, Moya A, Martínez-García M, Maldonado R, Fernández-Real J-M. 2022. Caudovirales bacteriophages are associated with improved executive function and memory in flies, mice, and humans. Cell Host Microbe 30:340-356.e8.

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    483: Recycling Resources Raises Robustness

    483: Recycling Resources Raises Robustness

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    Show notes:
    Microbe of the episode: Lactococcus virus sk1

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    Takeaways
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    Journal Paper:
    Szydlo K, Ignatova Z, Gorochowski TE. 2022. Improving the Robustness of Engineered Bacteria to Nutrient Stress Using Programmed Proteolysis. ACS Synth Biol 11:1049–1059.

     

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    Email questions or comments to bacteriofiles at gmail dot com. Thanks for listening!

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    482: Colony Concentric Clock Construction

    482: Colony Concentric Clock Construction

    This episode: Single-celled bacteria can act independently to create patterns and structure in their biofilm communities!

    Download Episode (9.6 MB, 14.0 minutes)

    Show notes:
    Microbe of the episode: Dictyostelium discoideum Skipper virus

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    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 they do often display interesting communal patterns and behaviors.

    In this study, bacteria growing in colonies on agar displayed a particular mechanism of pattern formation previously seen only in eukaryotes, called segmentation clock or clock and wavefront process. In this process, the cells in the colony are all acting individually without communication with each other, but nevertheless form a repeating ring structure in the colony as it grows, possibly allowing some measure of differentiation of cells that could help the community survive various challenges.
     
    Journal Paper:
    Chou K-T, Lee DD, Chiou J, Galera-Laporta L, Ly S, Garcia-Ojalvo J, Süel GM. 2022. A segmentation clock patterns cellular differentiation in a bacterial biofilm. Cell 185:145-157.e13.

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    481: Hijacker-Host Sequence Swap

    481: Hijacker-Host Sequence Swap

    This episode: Gene transfers between viruses and eukaryotes have happened many times throughout evolutionary history!

    Download Episode (7.5 MB, 10.9 minutes)

    Show notes:
    Microbe of the episode: Mycoplasma subdolum

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    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 transfers of genes from virus to host or from host to virus in the cells of all kinds of different eukaryotes. Some of these genes play important roles in the cell, helping to make them what they are.
     
    Journal Paper:
    Irwin NAT, Pittis AA, Richards TA, Keeling PJ. 2022. Systematic evaluation of horizontal gene transfer between eukaryotes and viruses. Nat Microbiol 7:327–336.

     

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    Email questions or comments to bacteriofiles at gmail dot com. Thanks for listening!

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    480: Bait Bottlenecks Bear Bacteria

    480: Bait Bottlenecks Bear Bacteria

    This episode: Human-based food used as bait by hunters can reduce bears' gut microbe diversity!

    Download Episode (5.9 MB, 8.6 minutes)

    Show notes:
    Microbe of the episode: Actinomadura verrucosospora

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    Takeaways
    Gut microbes are important for the health of most animals. In humans, many things can affect our gut microbe community, including diet, medications, and lifestyle. Eating a varied diet with diverse kinds of plant-based foods can maintain a healthy, functional community of many different kinds of microbe. However, eating mostly highly processed grain-based foods can reduce the diversity and functionality of the gut community.

    This is also true in bears. In this study, when bears consumed more processed, grain-based human foods via hunters leaving such foods out as bait, the gut communities in these bears had reduced diversity of microbes. The effects of this reduced diversity were not determined, but it is reasonable to assume it was not good for the bears’ overall health.
     
    Journal Paper:
    Gillman SJ, McKenney EA, Lafferty DJR. 2022. Human-provisioned foods reduce gut microbiome diversity in American black bears (Ursus americanus). J Mammal 103:339–346.

     

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    Email questions or comments to bacteriofiles at gmail dot com. Thanks for listening!

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    BacterioFiles
    enJuly 03, 2023