Show Notes
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 [email protected]
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Matters Microbial #141: How Tardigrades Survive What We Do To Them October 20, 2026 Today Dr. Molly Jane Kirk, postdoctoral scholar in the Department of Molecular, Cellular, and Developmental Biology at UC Santa Barbara, joins the quality quorum to discuss her research fascination with the biology and resilience of a microscopic multicellular eukaryote, the famous tardigrade.
Matters Microbial #140: Out of Many, One — Coral and Jellyfish Holobionts October 7, 2026 Today Dr. Monica Medina, Professor in the Department of Ecology and Evolutionary Biology at UCLA, joins the quality quorum to discuss how organisms are made up of myriad other organisms—the holonbiont concept. Dr. Medina and her research group focus on studying this in jellyfish and coral.
Matters Microbial #139: How Listeria Gets By With a Little Help From Its Friends September 23, 2026 Today Dr. Jasna Kovac, Huck Chair in Microbiomes in Food Safety and Associate Professor of Food Science at Penn State University (and active member of Penn State's One Health Microbiome Center) joins the quality quorum to discuss how understanding the microbiome in food processing facilities can help reduce the incidence of food borne illnesses, including Listeria. Host: Mark O. Martin Guest: Jasna Kovac Subscribe: Apple Podcasts, Spotify Become a patron of Matters Microbial! Links for this episode Here is an overview of Listeria as a microbe. Here is an overview of Listeria pathogenesis. A video showing "actin rockets" moving Listeria around inside of a eukaryotic cell. Overview from the CDC regarding Listeria. Prior #MattersMicrobial podcast about Listeria by Dr. Lisa Gorski. An overview of microbial food safety issues. Description of the cantaloupe associated Listeria outbreak. Description of the caramel apple Listeria outbreak. An overview of whole genome sequencing as a diagnostic tool. A video description of MIC (minimal inhibitory concentration) relationship between microbes and antimicrobials. An overview of biofilms. A prior #MattersMicrobial podcast about biofilms with Dr. Matthew Fields. The One Health Concept linking many aspects of everyday life to microbiology. A description of Sanger 16S rRNA sequencing. An overview of MPN (most probably number) analysis in microbiology. A video describing the very useful LIVE/DEAD dye approach in microbiology. Microbiology and sanitizers. An overview of EPS (extracellular polysaccharides). Description of SNPs (single nucleotide polymorphisms). An overview of the lineages of Listeria. A description of Dr. Kovac's approach to precision food safety. A nice description of Dr. Kovac's evaluation of tree fruit processing plants described in this podcast. A wonderful video presentation by Dr. Kovac. Dr. Kovac's academic website. The research laboratory website for Dr. Kovac and colleagues. Intro music is by Reber Clark Send your questions and comments to [email protected]
Matters Microbial #138: Sightseeing the Microbial World September 8, 2026 Today Dr. Monika Oli, Instructional Professor of the Department of Microbiology and Cell Science at the University of Florida joins the quality quorum to discuss how she teaches microbiology students to view the topic through a global lens as a study abroad program. Her approach demonstrates how travel enriches scientific understanding, broadens cultural perspectives, and prepares students to become globally engaged microbiologists equipped to address the challenges of an interconnected world.
Matters Microbial #137: The Living Skin of Our Planet August 25, 2026 Today Dr. Estelle Couradeau, Assistant Professor in the Department of Ecosystem Science and Management and the Huck Institutes of the Life Sciences at the Pennsylvania State University, joins the quality quorum today to discuss the role that the soil microbiome can play in terms of agriculture, moderating temperature, and protecting specific environments.