Matters Microbial #106: Cells Without Walls – Full-Frontal Bacteria September 6, 2025 Today, Dr. Dennis Claessen of Leiden University’s Institute of Biology joins the #QualityQuorum to discuss how some bacteria lose their cell walls, the costs and advantages of that strategy, and how such cells can shed light on antibiotic resistance and even pathogenesis! Host: Mark O. Martin Guest: Dennis Claessen Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode Website for the Institute for Biology at Leiden University in the Netherlands. The website of Micropia, the world’s best known (and perhaps only) museum devoted to microbial life, in Amsterdam, the Netherlands. The “Tardigrade Chair” at Micropia. The art of Dr. Lizah van der Aart. A video about the cell wall of bacteria. A useful overview of the cell wall of bacteria. A useful review article about the cell membrane of bacteria. An overview of peptidoglycan. The discovery of L-forms of bacteria, and Emmy Klieneberger-Nobel, who named them in 1935. A review article on L-forms (cell wall deficient) bacteria. An article relating L-forms of bacteria and the ability to resist certain antibiotics. Here is another article. An article suggesting that L-forms could shed light on the origins of life. An article suggesting that L-forms are a strategy for dealing with stress. An article from Dr. Claessen’s research group showing that L-forms of bacteria are often resistant to bacteriophage infection—and in a reversible fashion. A video presentation by Dr. Claessen. The faculty website of Dr. Claessen. The research website for Dr. Claessen’s group. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #105: Snails Farming Bacteria in the Deep Sea August 29, 2025 Let’s take a deep dive into chemoautotrophy! Today, Dr. Roxanne Beinart, Associate Professor of Oceanography at the University of Rhode Island, joins the #QualityQuorum to discuss how some marine creatures use bacterial symbioses to provide organic compounds for growth and reproduction. Host: Mark O. Martin Guest: Roxanne Beinart Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode An appreciation of the late Dr. Moselio (Elio) Schaechter from his friends at the blog “Small Things Considered.” A video from This Week in Microbiology appreciating Elio Schaechter. A video describing deep sea symbioses. A video by the great Dr. Colleen Cavanaugh about chemoautotrophy/chemosynthesis. An overview of chemoautotrophic strategies in the ocean. An overview of hydrothermal vents. A video review of thiotrophic (sulfur based) symbiotic associations. A video about hydrothermal vent exploration. A review of hydrothermal vent communities. Alvinella, the extremophilic bristleworm discussed in this episode (includes videos). An article by Dr. Beinart and colleagues, describing how a hydrothermal vent community is disrupted by a volcanic eruption. A report on the 2020 submarine volcano eruption discussed in this episode. An interesting article about studying deep sea symbioses, coauthored by Dr. Beinart. A great video by Dr. Beinart about her research. Dr. Beinart’s research team website. Dr. Beinart’s faculty webpage. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #104: Antibiotic “Tolerance” and Biofilms August 21, 2025 Today, Dr. Boo Shan Tseng, Associate Professor at the University of Nevada Las Vegas School of Life Sciences, joins the #QualityQuorum to discuss bacterial biofilms and antibiotic tolerance. Host: Mark O. Martin Guest: Boo Shan Tseng Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode A video overview of biofilms. A comprehensive review article on biofilms. An article describing the impact biofilms have on disease. An article describing the impact of biofilms on implanted medical devices. A link to the Center for Biofilm Engineering at Montana State University that has MANY links of interest. An overview of biofilm development. An overview of confocal laser microscopy. Studying biofilms in flow cells. An article about the role proteins play in biofilm formation, which intersects with the Tseng group’s research. The technique of single cell RNA seq. The technique of mRNA-FISH. An article about porins in bacteria, and how that can relate to antibiotic resistance. An article by Dr. Tseng and coworkers on the eDNA and biofilms discussed today. A lovely video of Dr. Tseng talking about the research she and her colleagues carry out in the laboratory. Dr. Tseng’s biography from the American Society for Microbiology. Dr. Tseng’s laboratory group website with wonderful links and images. Dr. Tseng’s faculty website. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #103: Giant Bacteria and Bigger Questions August 14, 2025 Today, Dr. Jean-Marie Volland, Assistant Professor at the University of California in Santa Barbara joins the #QualityQuorum to discuss the discovery and analysis of the (so far) largest bacterium known: Thiomargarita magnifica, which can be a centimeter long! Definitely #OMG and #WTM! Host: Mark O. Martin Guest: Jean-Marie Vollard Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode Here is a review article discussing the environmental persistence of antibiotic resistance genes. Here is a link to Episode 41 of this podcast, with Dr. Esther Angert, on the wily ways of Epulopiscium. A review article regarding “giant bacteria.” A video explaining the surface area versus volume issue discussed on this podcast. An interesting article exploring how much “territory” is within a bacterial cell; this is relevant to bacterial polyploidy. A review of Epulopiscium, the first of the giant bacteria described. Here is a video of Epulopisicum. An article describing polyploidy in Epulopiscium. A review of Thiomargarita nambiensis, another giant bacterium with an interesting strategy. Here is a video of T. nambiensis. An essay from “Small Things Considered” about the very, very strange world of Achromatium, which is so worth your time. The first report of Thiomargarita magnifica, the world’s largest bacterium (thus far) by Dr. Volland and coauthors. Here is a report on this discovery for novice micronauts. A great review about giant microbes by Dr. Volland. A more recent article on T. magnifica by Dr. Volland and colleagues. A video regarding T. magnifica. A video by Dr. Volland describing T. magnifica work. A lovely essay regarding how Dr. Volland and family trekked California searching for giant microbes. Don’t miss! The research lab website for Dr. Volland and colleagues, with so much interesting information. The faculty website for Dr. Volland at UC Santa Barbara. Intro music is by Reber Clark
Matters Microbial #102: Teaching Through the Issues with Microbes! July 31, 2025 Today, Dr. Davida Smyth, Professor of Biology and Deputy Director of the National Center for Science and Civic Engagement at Texas A&M University-San Antonio joins the #QualityQuorum to discuss her impressive work using microbiology to engage students at the intersection of cutting edge research and current events. #MicrobialLiteracy! Host: Mark O. Martin Guest: Davida Smyth Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode The American Society for Microbiology Carski Award website. The American Society for Microbiology Distinguished Lecturer website. The concept of “classroom agreements.” The 10:1 (microbial cells to human cells) story, and a related article. The 3-2-1 approach to learning in the classroom. Dr. Smyth’s “How Toilets Changed the World” class. The American Society for Microbiology Curriculum Guidelines. The National Science Foundation’s “Vision and Change” website describing improvements in biology education. The American Society for Microbiology profile for Dr. Smyth. A video seminar by Dr. Smyth describing open science in undergraduate education. The website for the National Center for Science and Civic Engagement. Dr. Smyth’s faculty website. Dr. Smyth’s superb research website. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #101: Electrifying News about Cable Bacteria July 25, 2025 Today, Dr. Nicole Geerlings from the University of Vienna in Austria joins the #QualityQuorum to discuss some of the wonderful work she and colleagues have carried out studying the wild, weird, and wonderful world of cable bacteria, which can conduct electricity over microbially enormous distances! Definitely time for #OMG and #WTM! Host: Mark O. Martin Guest: Nicole Geerlings Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode This just became available: a wonderful short introduction to day’s topic, the cable bacteria, from Asimov Press. It is an absolute must read for everyone interested. Here is a link to the Summer Science Program, a wonderful outreach program for high school juniors. An essay about Nobel Prize winning Albert Szent-Györgyi, who stated that life was a matter of electrons finding a place to rest. Here is a short video introduction to his work. A video introduction to microbial metabolism. A video introduction to electron transport. Remember that bacteria and archaea are VERY skilled at using different electron donors and acceptors than eukaryotic life. The really fun concept of the “Jagendorf Jump,” showing electron transport vs. pH in chloroplasts. An overview of the microbial fuel cell concept. Here is a nice overview I highly recommend. A commercial source for you to build your own microbial fuel cell. A DIY approach to building a MFC. An ESSENTIAL overview to the idea of electrons in microbial sediments. A review article about cable bacteria. Here is another fine review. This is a third great introduction to cable bacteria. And here is a video overview. An article by Dr. Geerlings and colleagues describing cable bacteria for new #Micronauts. HIGHLY RECOMMENDED. An review of stable isotope probing in microbiology. Here is a video seminar using SIP in microbiology. An overview of Nano-SIMS and how it is used in microbiology. Here is another review. A deeply wonderful article by Dr. Geerlings and colleagues suggesting that inactive cells with the “microbial cable” are still conducting electrons! Dr. Geerlings postdoctoral scholar website. Links and References on Cable Bacteria from Dr. Geerlings: 1. Here is a website from the group of Prof. Dr. Filip Meysman from the University of Antwerp, which includes a great video on the electron conductivity of cable bacteria. 2. The first paper describing redox half-reactions separated by long-distance electron transport. Nielsen, L. P., Risgaard-Petersen, N., Fossing, H., Christensen, P. B., and Sayama, M. (2010). Electric currents couple spatially separated biogeochemical processes in marine sediment. Nature 463, 1071–1074. doi: 10.1038/nature08790 3. The paper describing the discovery of cable bacteria. Look into the supplemental material for the excellent experimental set-up to prove that the cable bacteria are the ones doing the long-distance electron transport. Pfeffer, C., Larsen, S., Song, J., Dong, M., Besenbacher, F., Meyer, R. L., et al. (2012). Filamentous bacteria transport electrons over centimetre distances. Nature 491, 218–221. Doi: 10.1038/nature11586 4. A paper that dives into the conductivity of the cable bacteria network and shows that these fibres can conduct electrons just as well as a copper wire. Meysman, F. J. R., Cornelissen, R., Trashin, S., Bonné, R., Martinez, S. H., van der Veen, J., et al. 2019. A highly conductive fibre network enables centimetre-scale electron transport in multicellular cable bacteria. Nat. Commun. 10:1–8. doi: 10.1038/s41467-019-12115-7 5. This paper describes how cable bacteria activity generates a layer of iron oxyhydroxides on the top of the sediment layer and how this delays the release of sulfide into the water column for several weeks in a seasonally hypoxic basin in the Netherlands. Seitaj, D., R. Schauer, F. Sulu-Gambari, et al. 2015. “Cable Bacteria Generate a Firewall Against Euxinia in Seasonally Hypoxic Basins.” Proceedings of the National Academy of Sciences of the United States of America 112: 13278–13283. 6. This paper describes how the catabolic division of labor is coupled to an anabolic division of labor where cells reducing oxygen cannot grow and therefore provide a “community service” for the rest of the filament. Nicole M. J. Geerlings, Cheryl Karman, Stanislav Trashin, Karel S. As, Michiel V. M. Kienhuis, Silvia Hidalgo-Martinez, Diana Vasquez-Cardenas, Henricus T.S. Boschker, Karolien de Wael, Jack J. Middelburg, Lubos Polerecky, and Filip J.R. Meysman. Division of labor and growth during electrical cooperation in multicellular cable bacteria. Proc. Natl. Acad. Sci. U.S.A. 117, 5478–5485. Doi: 10.1073/pnas.1916244117 Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #100: What’s the Buzz on Phage Therapy for Honeybees? July 14, 2025 Today, Dr. Heather Hendrickson from the University of Canterbury in New Zealand joins the #QualityQuorum to discuss the research she and her team are conducting on bacteriophage therapy to protect vulnerable honeybees from bacterial infections. Host: Mark O. Martin Guest: Heather Hendrickson Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode Here is the website for a former undergraduate research student of mine, Dr. Paula Welander, now a professor and administrator at Stanford University. Yes, I am proud. Here is a link to another former undergraduate research student of mine, Dr. Krista Venecia Edmiston, now a professor at California Health Sciences University. Yes, I am proud. A review on cell shape in bacteria. A review on the cytoskeleton of bacteria and archaea. I am a great admirer of Dr. John Roth, and his clearheaded and direct approach to microbial genetics. Here is his academic website with many publications. An article about the causative agent of American Foulbrood, Paenibacillus larvae. An overview of American Foulbrood’s impact on honeybees. The honeybee lifecycle. Beemites and honeybees. A video overview of bacteriophage therapy against bacterial diseases. An explainer of bacteriophage plaques. A video overview of lytic versus lysogenic bacteriophages. Dr. Graham Hatfull and his simply amazing SEAPHAGEs program, teaching so many people about isolating and studying bacteriophages. An article from Dr. Hendrickson’s laboratory exploring cell shape in bacteria. An article from Dr. Hendrickson’s laboratory explaining the importance of protecting honeybees from American Foulbrood, and the approach her laboratory uses. An article from Dr. Hendrickson’s laboratory describing a community based approach to search for bacteriophages of Paenibacillus larvae. An article from Dr. Hendrickson’s laboratory analyzing the types of Paenibacillus attacking bacteriophages isolated in New Zealand. An article from Dr. Hendrickson’s laboratory describing an improved method for isolating bacteriophages. A truly great video from Dr. Hendrickson some years ago, explaining her research. This is a “must see.” Dr. Hendrickson’s faculty webpage. Dr. Hendrickson’s informative research group website. This section of Dr. Hendrickson’s research group website is devoted to outreach, and so very worth your time. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #99: Albert Kluyver—Microbial Unity and Diversity in Metabolism July 10, 2025 Today, Dr. Dianne Newman of Caltech joins the #QualityQuorum live at ASM Microbe in Los Angeles, to discuss the role that Albert Kluvyer played in helping microbial scientists to understand the unity and diversity to be found in microbial metabolism. Host: Mark O. Martin Guest: Dianne Newman Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode A review article by Roberto Kolter about the history of microbiology. An overview of the “Delft School” of microbiology. Here is another article on that topic. The 1924 article by Albert Kluyver that Dr. Newman references—very much worth you time. A video overview of microbial metabolism. Here is a recent article on that topic. A short biography of Albert Kluyver. Here is another article on that topic. A wonderful 2023 video seminar by Dr. Newman exploring the unity and diversity of microbial metabolism. Much recommended. Dr. Newman’s faculty website. Dr. Newman’s very impressive research group website. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #98: Nesting Dolls of Endosymbiosis July 3, 2025 Today, Dr. John McCutcheon of Arizona State University joins the #QualityQuorum to discuss the work he and his research group do to investigate the strategies by which microbes become symbionts of other cells. After all, the mitochondria and chloroplasts of eukaryotic cells, including yours, were once bacteria! Host: Mark O. Martin Guest: John McCutcheon Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode A video about the symbiosis of Hydra virdissima, which captured my heart when I was young. Look at those symbiotic algae! Here is an overview of this topic. A video describing the Rhizobium – legume nitrogen fixing symbiosis in all of its glory—by my PhD advisor, the great Dr. Sharon Long. Here is an overview of this topic. An appreciation of Paul Buchner’s very important book, “Endosymbiosis of Animals with Plant Microorganisms.” A wonderful review by Dr. McCutcheon on how symbioses form. A wonderful essay by Ed Yong about an event that made eukaryotic cells possible: how bacteria became mitochondria. A story about an anaerobic protist that lost its mitochondria completely. A bacterial symbiont of mitochondria, the “midichlorian.” The recent discovery of a new integrated symbiont that has become an organelle, the nitrosome. The “X-bacteria” and amoebae story. A retrospective on endosymbiosis, and Paramecium based on Tracey Sonneborn’s work. An essay on aphids and bacteria. An article on the Moranella/Tremblaya symbiosis. An article on “bacteria inside other bacteria” found in several symbioses, written by Dr.McCutcheon and colleagues. Genomic instability in bacterial endosymbionts. An article on cicadas and bacterial endosymbionts from Dr. McCutcheon and colleagues. An article on mealybugs and bacterial endosymbionts from Dr. McCutcheon and colleagues. Dr. McCutcheon’s thoughts on his career path (so worth reading). The Center for Mechanisms of Evolution research institute in which Dr. McCutcheon works. Dr. McCutcheon’s faculty website. Dr. McCutcheon’s (and his research team’s) wonderful research website. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #97: Microbes in the Air (Way) June 27, 2025 Today, Dr. Ari Kozik, Assistant Professor at the University of MIchigan joins the #QualityQuorum to discuss the work she and her research group do to investigate microbes living within the lung and their relationship to health as well as microbiology outreach and representation. Host: Mark O. Martin Guest: Ari Kozik Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode A wonderful discussion of airway microbes. A thought provoking article about microbes in our breath! Geography of mouth to lung and relevance to health. Relevance and definition of the term “microaspiration.” Some general characteristics of anaerobic bacteria A commercial video explaining the basics of anaerobic chambers An article about the airway microbiome A video overview about biofilms Kombucha sculpture as discussed briefly. A relevant article from Dr. Kozik’s and coworkers. A video from This Week in Virology including Dr. Kozik about representation in the microbial sciences (very important to watch). Dr. Kozik’s important efforts in science outreach. Dr. Kozik’s faculty website. Dr. Kozik’s research group website. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #96: Molecular Microbiology in High Schools June 19, 2025 Today, Bob Kuhn, biotechnology teacher at the Fulton County Schools Innovation Academy STEM high school in Alpharetta, Georgia joins the #QualityQuorum to discuss his strategies for teaching molecular microbiology skills and concepts to high school students — and why that matters. Host: Mark O. Martin Guest: Bob Kuhn Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode An article on Mr. Kuhn’s original microbiological interest: salt marsh foraminifera. Another interest: a video of the beautiful organism Volvox. An overview of the fantastic world of protists. A classroom CURE that Mr. Kuhn uses: the Tiny Earth program. A classroom CURE that Mr. Kuhn uses: the SEAPHAGES program. A classroom CURE that Mr. Kuhn uses: the Evolving Stem program. A classroom CURE that Mr. Kuhn uses: the Discover the Microbes Within program. Mr. Kuhn’s classroom received help from the University of Georgia Microscopy Center. A video of the Wolbachia Project with which Mr. Kuhn has collaborated for years. An overview of wonderful and various isopods, including the “roly polies” used in some Wolbachia work. The Journal of Emerging Investigators, in which some of Mr. Kuhn’s high school students have published. The LTEE program that studies evolution in E. coli. The Experiment.com program that supported some of Mr. Kuhn’s students. The very inspirational MEGAplate video that demonstrates how quickly antibiotic resistance can occur. Innovation Academy STEM program in Georgia, where Mr. Kuhn works with high school students. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #95: Bacteria and Aphids — A Symbiotic Story June 12, 2025 Today, Dr. Tory Hendry, Associate Professor of Microbiology at Cornell University, joins the #QualityQuorum to tell us about the relationship between plant munching aphids and fluorescent Pseudomonas . . . and why we should care. Host: Mark O. Martin Guests: Tory Hendry Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode An overview of siderophores in microorganisms. An essay about aphid life cycle and characteristics. An article describing parthenogenesis in aphids. An essay describing aphids and color vision. The agricultural costs of aphids as pests. An article describing aphids and one type of bacterial symbiont. An overview of microbes of the phyllosphere. An overview of quorum sensing. An overview of pyoverdin, a fluorescent siderophore. An old essay I wrote for the Small Things Considered blog about semiochemicals, bacterial, and insect predation. A nice description of the work Dr. Hendry talked about during today’s podcast. The actual article by Dr. Hendry and collaborators. A preprint by Dr. Hendry’s research group, following up on the above research. Dr. Hendry’s faculty website. Dr. Hendry’s research group website (with SO MANY cool projects to think about, including the topic discussed today). Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #94: One Health and Microbiomes Everywhere June 5, 2025 Today, Dr. Seth Bordenstein and Dr. Nichole Ginnan of Pennsylvania State University join the #QualityQuorum to tell us about their new publication linking One Health to the myriad microbiomes that exist all around us through the lens of the holobiome—and an opportunity to see the world in a different fashion. Host: Mark O. Martin Guests: Seth Bordenstein and Nichole Ginnan Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode Michele Banks microbially themed art can found at her Etsy site. Highly recommended! The paper under discussion today, with Dr. Ginnan as first author. You will see that coauthors include Dr. Bordenstein, and two previous visitors to the #MattersMicrobial podcast! Thank you Erika and Francisco. Dr. Bordenstein’s first podcast with #MattersMicrobial for those who missed it. A review of the One Health concept. The One Health Microbiome Center at Penn State. A very clear overview of the holobiont concept and biology, authored by Dr. Bordenstein and colleagues. Another longer review on this topic. The faculty website for Dr. Ginnan. The faculty website for Dr. Bordenstein. The research website for Dr. Ginnan. The research website for Dr. Bordenstein. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #93: Preventing Antibiotic Resistance May 29, 2025 Today’s episode was an in-person podcast at the University of Texas Austin! Dr. Despoina Mavridou, Assistant Professor of Molecular Biosciences, joins the #QualityQuorum to discuss how her research group improves antibiotic effectiveness by impeding protein folding, and why this matters in the fight against antimicrobial resistance. Host: Mark O. Martin Guest: Despoina Mavridou Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode Here is a link to a wonderful video of the #LuxArt by UT-Austin students during my visit. Please give it watch and enjoy the creativity and positive #MicrobialPR. An effective TED talk by science journalist Maryn McKenna describing the threat of AMR in an accessible fashion. A CDC report on the growing threat of AMR. A review article about antibiotics. An overview of how bacteria become resistant to antibiotics. A very recent review of the cell wall of bacteria—often the target of antibiotics. A video overview of beta-lactam antibiotics and resistance mechanisms. An overview of how protein folding is related to activity of proteins…including AMR gene products. A wonderful article by Dr. Mavridou and coworkers, describing how altering protein folding in bacteria can make them more vulnerable to antibiotics. A less technical version of the above article; well worth your reading. Dr. Mavridou’s faculty website. Dr. Mavridou’s research group website, which is most interesting. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #92: Microbial Metabolism in Extreme Places May 22, 2025 Today, Dr. Valerie DeAnda Torres, Assistant Professor of Microbiology and Cell Science at the University of Florida (and National Geographic Explorer), joins the #QualityQuorum to tell us about the research her team does, studying the evolution of metabolic pathways in extreme environments . . . and why these are important to geochemical cycling. Host: Mark O. Martin Guest: Valerie DeAnda Torres Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode The Etsy vendor making the beautiful microbial pins I have mentioned. A link to Sebastian Cocobia’s site where the beautiful E. coli strains I referenced can be obtained. The beauty and mystery of Paenibacillus colonies. A video showing a colony of Myxococcus consuming a colony of E. coli. A fun video of tardigrades singing “Happy birthday” by a former undergraduate student of mine, Dr. Jake Shaffer. The National Geographic Explorer program, which includes Dr. DeAnda Torres. The deep sea submersible Alvin, in which Dr. DeAnda Torres has dived! An overview of methanogenesis, one of the pathways that Dr. DeAnda Torres’ research group studies. A review of biogeochemical cycles in the deep ocean. The work of my former undergraduate research student, Dr. Paula Welander, on membrane biosignatures in ancient rocks. A recent review of the Asgard archaea, that may be our ancient ancestors. Some recent work by Dr. DeAnda Torres and collaborators on the Asgard archaea. One of the research cruises in which Dr. DeAnda Torres participated. During one cruise that included an Alvin dive to a hydrothermal vent, Dr. DeAnda Torres and scientists working with her described their work in this livestream partially in Spanish. Dr. DeAnda Torres will be part of some upcoming collaborative research cruises, seen here. Here is an article and video describing some of the collaborative work Dr. DeAnda Torres carries out, studying microbial breakdown of PFAS chemicals in marine sediment. A link to the faculty website of Dr. DeAnda Torres. A link to the research website of the DeAnda Torres group. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #91: You Are What Your Genes Feed Your Microbiome May 16, 2025 Today, Dr. Emily Davenport, Assistant Professor in the Department of Biology and Huck Institutes of the Life Sciences at Penn State University, joins the #QualityQuorum to tell us about the research her team does, studying how our own genes impact our microbiomes. Host: Mark O. Martin Guest: Emily Davenport Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode A description of GWAS (“Genome Wide Association Study”). Here is an introductory video about the concept. An explainer on organoids. An essay about the diversity of the host microbiome (i.e. is there a “healthy” microbiome?). An article of the work of Dr. Sarkis Mazamian on how individual host genes and bacterial genes can impact the microbiome. A nice write up for Dr. Mazamian’s work showing how host genes and bacterial genes can work together…or not. An oldish video of how the infant microbiome develops over time by Dr. Rob Knight’s research group. An article on the same topic from Dr. Ruth Ley. An essay on the mucosal microbiota, rather than the fecal microbiome. An interesting member of the human microbiome, Akkermansia that might be related to obesity. Another interesting member of the human microbiome, Bifidobacterium, which appears to be associated with host lactose metabolism. Yes, there is a Giant Microbes plush toy. An overview of the impact of host genetics on the microbiome by Dr. Davenport. A definition of heritability. An overview of the Hutterites and how their study has advanced genetics. An explainer of the power of twin studies in genetics. A fascinating article about ancient dental plaque microbiome by Dr. Davenport and others. Dr. Davenport’s faculty website. Dr. Davenport’s research group website. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #90: Using Soil Microbiomes in Sustainable Agriculture May 8, 2025 Today, Dr. Francisco Dini Andreote, Assistant Professor of Phytobiomes at Penn State, joins the #QualityQuorum to tell us about the microbiome of plants and the soil, and how understanding that relationship can improve agriculture. Host: Mark O. Martin Guest: Francisco Dini Andreote Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode An overview of the Type 6 Secretory System of bacteria—almost like a microbial switchblade knife. A wonderful video of the T6SS made by a student in my own microbiology course some time ago. A video introduction to the Rhizobium-legume symbiosis and why you should care about it (by my PhD advisor from long ago, Dr. Sharon Long). A more comprehensive review article on the Rhizobium-legume symbiosis. The chemical signal of geosmin, and how it might be used by other organisms. Ecological succession in the development of sauerkraut. A must read essay by Carl Zimmer likening the human body to a number of ecological niches. The developing field of agroecology. A reminder about the “One Health” concept. Mycorrhizae and plant nutrition. Chemical communication within the soil. A fun remembrance of Norman Borlaug, who urged us to “listen” to plants. An overview of the root microbiome. The “superorganism” concept versus the “holobiome” concept.. Striga, a parasite of crop plants. Chemical communication and Striga. An interesting and relevant publication from Dr. Dini Andreote’s research group, describing how the root microbiome could help agriculture. Dr. Dini Andreote’s faculty website. Dr. Dini Andreote’s very wonderful research team website. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #89: Can AI Point Us to New Antibiotics May 1, 2025 Today, Dr. Amir Mitchell, Associate Professor of Systems Biology at the University of Massachusetts Medical School, joins the #QualityQuorum to discuss using artificial intelligence to develop new and effective antibiotics in our endless battle against drug-resistant microbes. Host: Mark O. Martin Guest: Amir MItchell Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode An article exploring the impact of the microbiome on drug effectiveness. A blog post discussing the relationship between the gut microbiome and creosote metabolism in wood rats. An essay about the threat of antibiotic resistance. A more scholarly article on this topic. A CDC report of the rise of antibiotic resistance. A very moving TED talk on this topic. An overview of antibiotic resistance mechanisms. A video from Dr. Michael Baym’s laboratory demonstrating how rapidly antibiotic resistance can occur. An essay discussing the use of artificial intelligence in the search for new antibiotics. An article from Dr. Mitchell’s research group discussing his approach to identity new antimicrobial compounds. Dr. Mitchell’s faculty website. Dr. Mitchell’s very interesting research team website. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #88: Microbial Interactions in Cystic Fibrosis April 24, 2025 Today, Dr. Reed Stubbendieck, Assistant Professor of Microbiology & Molecular Genetics at Oklahoma State University joins the #QualityQuorum to discuss how microbes and the host communicate with one another in the cystic fibrosis lung. Host: Mark O. Martin Guest: Reed Stubbendieck Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode An overview of cystic fibrosis as a disease with a genetic link. A review of the microbiome of the cystic fibrosis lung. An overview of biofilms. An interesting role for extracellular DNA itself as a “building block” of biofilms. An overview of polymicrobial communities. Life in mucus—an interesting essay. An overview of Pseudomonas aeruginosa. Pseudomonas and the siderophore pigment pyoverdin which is not only about iron, but also bacterial conflict and cooperation. An interesting overview of microbe-microbe interactions, often called “sociomicrobiology,” and an introductory article on this topic. A review of the nasal microbiome. The organism Rothia, understudied and of interest to Dr. Stubbendieck’s research group. Some work from Dr. Stubbendieck’s group describing how Rothia is helpful in inhibiting some disease causing bacteria. The organism Dolosigranulum pigrum, also understudied and of interest to Dr. Stubbendieck’s research group. More work from Dr. Stubbendieck’s group with another possibly probiotic bacterium, Dolosigranulum pigrum, that may protect against disease causing microbes. Dr. Stubbendieck’s faculty website. Dr. Stubbendieck’s very interesting research group website. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com
Matters Microbial #87: Dietary Protein and the Microbiome April 17, 2025 Today, Dr. Manuel Kleiner, Associate Professor of Microbiomes and Complex Microbial Communities at North Carolina State University, joins the #QualityQuorum to discuss how diet can influence the microbiome in fascinating ways. Host: Mark O. Martin Guest: Manuel Kleiner Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode An overview of “pink pigmented facultative methylotrophs,” which can lead to wonderful “leaf prints.” Gnotobiotic versus “germ-free” animals. A solid review of the gut microbiome and the relationship to health. An article describing how proteins are digested by the microbiota. A description of glycan degrading enzymes and the gut microbiome. An overview of mucin. Description of metaproteomics by Dr. Kleiner. Description of metagenomics. Gut microbiota and dysbiosis. An overview of inflammatory bowel disease. An overview of Bacteroides thetaiotaomicron. An overview of Akkermansia muciniphila. The possibility of microbes “farming” us for mucus! The wide ranging and deeply fascinating website for Dr. Kleiner’s research group. Dr. Kleiner’s faculty website. Intro music is by Reber Clark Send your questions and comments to mattersmicrobial@gmail.com