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  • The Gut Healing Power of Microbes and Cruciferous Vegetables
    2025/10/24
    Episode Summary Sue Ishaq, Ph.D., Associate Professor of Microbiomes at the University of Maine, discusses how gut microbes transform seemingly inert plant compounds—like glucosinolates found in broccoli—into powerful anti-inflammatory agents such as sulforaphane. Her research dives into the fascinating interplay between diet, cooking methods and the diversity of the gut microbiota, revealing how these factors influence the body's ability to produce health-promoting molecules. Links for This Episode
    • mSystems paper: Early life exposure to broccoli sprouts confers stronger protection against enterocolitis development in an immunological mouse model of inflammatory bowel disease.
    • mSystems paper: Steamed broccoli sprouts alleviate DSS-induced inflammation and retain gut microbial biogeography in mice.
    • Current Developments in Nutrition paper: Current knowledge on the preparation and benefits of cruciferous vegetables as relates to in vitro, in vivo, and clinical models of Inflammatory Bowel Disease.
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    43 分
  • Preventing Foodborne Pathogens With Plant-Derived Compounds with Karl Matthews
    2025/09/25
    Karl Matthews, Ph.D., Professor of Microbial Food Safety at Rutgers University, discusses ways to eliminate pathogens like Salmonella, E. coli O157:H7 and Listeria from fresh fruits and vegetables. He highlights the importance of preventative measures from farm to table, including the use of water antimicrobials, like chlorine, and photosensitizers, like curcumin. Watch this episode: https://youtu.be/6Wkef9RyUVE Ashley's Biggest Takeaways We consume billions of microorganisms in the food that we eat each day.Fresh fruits and vegetables that are not thermally processed are likely to carry a higher microbial load than cooked foods.Many of those microbes are not concerning to human health. However, when pathogens of human health concern are present, the food can become unsafe to eat.Scientists use many methods from pre-harvest through post-harvest to keep food free of human pathogens.Water antimicrobials, such as chlorine, and photodynamic inactivation using photosensitizers, such as curcumin, are 2 preventative measures that Matthews and colleagues are investigating.Curcumin is a natural chemical compound found in the turmeric plant. It is responsible for giving tumeric its yellow color.Curcumin is also a photosensitizer, meaning that it can absorb light energy and transfer it to another molecule to initiate chemical reactions that produce cytotoxic singlet oxygen. Featured Quotes When I look at [what makes fruits and vegetables safe to eat] as far as from a microbiological perspective, it's are they free of pathogens of human health concern? And so, we might think about organisms, such as Salmonella or the Shiga toxin producing E coli or Listeria. There are a number of processes and initiatives that are put into place, from the pre-harvest through post-harvest levels to try to ensure that the product is not contaminated with microorganisms of human health concern. Each day, we're consuming literally billions of microorganisms in the foods that we eat, and particularly the raw fruits and vegetables that we're eating that are not being thermally processed in any fashion by which you might reduce the microbial load. Oftentimes we think about the bacteria that might well be there. But we do know that there's viruses that could be present. There's certain type of protozoa that might be present. Many of us know of norovirus and the concerns associated with that particular pathogen. So, there's a multitude of microorganisms that might well be associated with fresh fruits and vegetables, but there's really a very limited number or types that are actually of concern from a human health standpoint. In my program, we're working on E. coli O157:H7, in particular. It's a certain serotype of E. coli, a diarrheagenic E. coli, what's also known as a Shiga toxin-producing E. coli. We work with Salmonella, and we work with Listeria monocytogenes, but there's other microorganisms, such as Campylobacter, Yersinia, Staphylococcus aureus. All of those types of pathogens can also be associated with foods—and different types of foods, at that—and be of concern to the general public—the consumer. If we look at a lot of the processing of foods that are taking place, not only here in the United States, but globally, many times, what will happen is they're utilizing some type of a water antimicrobial, and I stress that because, oftentimes, these antimicrobials are added to the water to control the microbial load in the water. So, ultimately, you're not basically putting on water and putting on a whole load of microorganisms along with it. And also, you can prevent cross contamination through that. Here in the U.S. and elsewhere, we'll often put additional chlorine into the water. So, let's say we're increasing the chlorine concentration to 20 parts per million, or 50 parts per million, or maybe in poultry processing, they're utilizing peracetic acid. These are 2 common antimicrobials that are being used. What we wanted to do is find out could we utilize some other types of methods that might well control microorganisms on the commodity itself? And that's where we started looking at photodynamic inactivation and coupling that with the use of a photosensitizer. And in this particular case, the photosensitizer we were using was curcumin. The reason for working with curcumin is that it's naturally used in foods as a food dye. It's also used as a flavoring agent, and so forth. So, it's there, and it's being used—not just in the U.S., but [also] globally. And we thought we would try to see if we utilize this compound, could we have an additive effect to it? If you apply certain wavelengths of light, you can inactivate microorganisms, but if you apply that wavelength to something like a photosensitizer type molecule (curcumin), you could generate singlet oxygen molecules. And those singlet oxygen molecules would act like little explosions on the cell membrane and basically blow it apart and, therefore,...
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    59 分
  • Early Microbial Life with Michael Lynch and Vaughn Cooper
    2025/08/22

    Michael Lynch, Ph.D., Director of the Center for Mechanisms of Evolution at Arizona State University and Vaughn Cooper, Ph.D., professor of Microbiology and Molecular Genetics at the University of Pittsburgh, School of Medicine, examine the origins and trajectory of early microbial life (EML) and discuss the collaborative report between the American Academy of Microbiology and the Gordon and Betty Moore Foundation, which explores the journey of life on Earth, from non-living chemical compounds to early unicellular life, to the vast diversity of organisms we see today.

    This episode is brought to you by the American Academy of Microbiology, a think tank at American Society for Microbiology and the Gordon and Betty Moore Foundation, which has been dedicated to advancing scientific discovery for the past 25 years.

    Links for This Episode:
    • Project Report Early Microbial Life: Our Past, Present and Future.
    • Article: The Great Oxidation Event: How Cyanobacteria Changed Life.
    • MTM Podcast: From Hydrothermal Vents to Cold Seeps: How Bacteria Sustain Ocean Life With Nicole Dubilier.
    • Take the MTM listener survey!
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    40 分
  • How FMTs, Coprophagia and the Milk Microbiome Inform Wildlife Conservation With Sally Bornbusch
    2025/07/15

    Sally Bornbusch, Ph.D., is an NSF postdoctoral fellow in biology conducting microbial ecology research in animal care and conservation at the Smithsonian National Zoo & Conservation Biology Institute. She discusses how FMTs are being used to mitigate health concerns in wild animals in captivity, shares key findings about the milk microbiome from the Smithsonian milk repository, the largest collection of exotic animal milks in the world, and explains the science behind eating poo (Coprophagia).

    Links for This Episode
    • Why Do Animals Eat Poop? (And Why It Might Be a Good Thing).
    • Faeces as food: a framework for adaptive nutritional coprophagy in vertebrates.
    • Even Monkeys Should Eat Their Vegetables.
    • Take the MTM listener survey!
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    48 分
  • Agnostic Diagnostics and the Future of ASM Health With Dev Mittar
    2025/05/30

    Dev Mittar, Ph.D., Scientific Director of the ASM Health Scientific Unit discusses the use of metagenomic next generation sequencing to develop agnostic diagnostic technology, giving scientists and clinicians alike, a tool to diagnose any infectious disease with one single test. He also discusses how the ASM Health Unit is empowering scientists and leveraging microbial science innovations to address critical global health challenges and improve lives worldwide.

    Ashley's Biggest Takeaways
    • The Division of Research, Innovation and Ventures is a small entrepreneurial arm of BARDA that takes on early-stage projects with high potential of turning into medical countermeasures.
    • Prior to his role as Scientific Director for ASM Health, Mittar worked as a health scientist and program officer at DRIVe, where he focused on advancing high-impact science.
    • He is particularly passionate about his work to develop agnostic diagnostics—a single test that uses metagenomic next generation sequencing to identify any pathogen from 1 clinical sample.
    • Mittar discusses applications for this technology in surveillance (pandemic preparedness), variant detection, AMR and clinical settings (diagnosing complicated infections where etiology is not clearly defined).
    • He also shares how a recent bout with illness emphasized the value and potential of this technology to save money, time, pain and suffering of the patient.
    • Agnostic diagnostics can also help prevent the overuse/misuse of antibiotics, which are key factors in the spread of antimicrobial resistance.
    • Furthermore, when this technology is coupled with the use of metatranscriptomics, it can provide information about the patient's immune profile that can be helpful in developing personalized treatment strategies, as opposed to a one-size-fits-all approach.
    • ASM is organizing around 3 scientific units, ASM Health, ASM Mechanism Discovery and ASM Applied and Environmental Microbiology.
    • These units will empower researchers and scientists to use science make a difference in the world and provide a forum for them to come together to shape the future of the field.
    Links for This Episode
    • Learn More About ASM's Scientific Units.
    • Join the Conversation on ASM Connect, our online community platform.
    • Browse Volunteer Opportunities.
    • Become an ASM Member.
    • Register for ASM Microbe 2025.
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    42 分
  • Implementing a National Action Plan to Combat AMR in Pakistan With Afreenish Amir
    2025/05/09
    Episode Summary Afreenish Amir, Ph.D., Antimicrobial Resistance (AMR) Project Director at the National Institute of Health in Pakistan, highlights significant increases in extensively drug-resistant typhoid and cholera cases in Pakistan and discusses local factors driving AMR in Asia. She describes the development and implementation of a National Action Plan to combat AMR in a developing country, emphasizing the importance of rational antimicrobial use, surveillance and infection control practice. Ashley's Biggest Takeaways AMR is a global and One Health issue.Pakistan has a huge disease burden of AMR.Contributing factors include, but are not limited to, overcrowding, lack of infection control practices, poor waste management practices and over-the-counter prescription practices.Promoting the rational use of antimicrobials is imperative at all levels—from tertiary care to primary care practitioners.Typhoid and cholera are high-burden infections in Pakistan, with typhoid being a year-round issue and cholera being seasonal.A holistic approach, involving various sectors and disciplines, is necessary in order to address the global AMR threat.Amir highlights the need for better communication and collaboration to bridge gaps and build trust between different organizations. Featured Quotes: I've been working at the National Institutes of Health for the last 7 years now. So, I've been engaged in the development and the implementation of the national action plan on AMR, and that gave me the opportunity to explore the work in the field of antimicrobial resistance. Reality of AMR in Pakistan [Pakistan] is an LMIC, and we have a huge disease burden of antimicrobial resistance in the country right now. A few years back, there was a situational analysis conducted, and that has shown that there is presence of a large number of resistant pathogens within the country. And National Institutes of Health, they have started a very standardized surveillance program based upon the global antimicrobial use and surveillance system back in 2017. And [those datasets have] generated good evidence about the basic statistics of AMR within the country. So, for example, if I talk about the extensively drug-resistant typhoid, typhoid is very much prevalent in the country. Our data shows that in 2017 there were 18% MDR typhoid cases through the surveillance data. And in 2021 it was like 60%. So that has shown that how the resistance has increased a lot. A number of challenges are associated with this kind of a thing, overcrowded hospitals, poor infection prevention and control (IPC) measures. So, there is AMR within the country—there's a huge burden—and we are trying to look for the better solutions. Local Factors Driving AMR Bacteria, they do not know the borders. We have a close connection with the other Asian countries, and we have a long border connected with the 2 big countries, which are Afghanistan and India and Bangladesh and China. So, we see that it's not limited to 1 area. It's not regional. It’s also a history of travel. When the people travel from one area to the other, they carry the pathogen as a colonizer or as a carrier, and they can infect [other] people. So, it's really connected, and it's really alarming as well. You never know how the disease is transmitted, and we have the biggest example of COVID—how things have spread from 1 country to the other, and how it has resulted in a massive pandemic. AMR is similar. We have seen that it's not limited to 1 region. We are part of this global community, and we are contributing somehow to the problem. First, I'll talk about the health care infrastructure. We do have the capacities in the hospitals, but still, there's a huge population. Pakistan is a thickly populated country. It's a population of around 241 million. And with the increasing population, we see that the infrastructure has not developed this much. So now the existing hospitals are overcrowded, and this has led to poor infection control practices within the hospitals. The staff is not there. In fact, ID consultants are not available in all the hospitals. Infection control nurses are not available in all the hospitals. So, this is one of the main areas that we see, that there is a big challenge. The other thing that can contribute is the poor waste management practices. Some of the hospitals—private and public sectors—they are following the waste management guidelines—even the laboratories. But many of the hospitals are not following the guidelines. And you know that AMR is under one health. So, whatever waste comes from the hospital eventually goes to the environment, and then from there to the animal sector and to the human sector. [Another big] problem that we are seeing is the over-the-counter prescription of antimicrobials. There is no regulation available in the country right now to control the over-the-counter prescription of antibiotics. They are easily available. People are taking...
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    38 分
  • Discovering Fossilized Microbes in Antarctic Ice Cores With Manuel Martinez Garcia
    2025/03/14
    Manuel Martinez Garcia, Ph.D., a professor of microbiology in the Physiology, Genetics and Microbiology Department at the University of Alicante in Spain, paints a picture of what microbial life looked like thousands of years ago by analyzing microbial genomic signatures within ice cores collected from the Antarctic ice shelves in the 1990s. Links for the Episode New avenues for potentially seeking microbial responses to climate change beneath Antarctic ice shelves – mSphere paper. Viruses under the Antarctic Ice Shelf are active and potentially involved in global nutrient cycles – Nature communications article. Manuel Martinez Garcia's Lab website. How stable is the West Antarctic Ice Shelf? – Press Release from Alfred Wegener Institute.Take the MTM listener survey! Watch this episode: https://youtu.be/CHCMO74_gIY Ashley's Biggest Takeaways There is a unique habitat beneath Antarctic ice shelves, where microbes live without light and rely on unusual energy sources. Ice cores from these Antarctic ice shelves can preserve fossilized genomic records of microbial life from long ago. Comparing past and present samples can help us understand how microbial life is responding to environmental stressors, like temperature changes and acidification, over time.It can also provide key insights to changes in biodiversity. Featured Quotes: Motivation for the Research Ice shelves are like massive floating ice that are in Antarctica, mainly. They can be as big as, for example, France, the country. So, they are super big—they are enormous. And they can be as thick as, let's say, 1000 meters. So, this is a massive [piece of] ice that we have in our planet. And beneath that massive ice, we can have a very peculiar and a special habitat in which microbes live without light. They have to manage, to thrive and reproduce, without using a standard energy like we have on the surface of the sea or in the forest, where we have light that is driving and providing the energy for the ecosystem. But in this case, these ecosystems are totally different. [The ice shelves] are deep and interconnected. Basically, there are different oceanic currents, for example, there is one Circumpolar Current that surrounds Antarctica, and there are also other currents that basically go from the bottom to the surface, moving, you know, all the water masses. The interesting part of this story is that every single second in our lives, this sea that is beneath the platform, the ice shelf, is frozen over and over, and then we have different layers of antiquity that preserve the microbes that are living in the ocean. So, for example, let's say, 1000 years ago, the sea water was frozen, and then we can find a layer beneath the Antarctica ice shelf, where these microbes are preserved and frozen. Basically, it's like a record—a library of microbes, fossil records of microbes—from the past ocean, from 1000 years ago until present, more or less. And then we can go to these records, to these layers of frozen sea water, and pick these samples to somehow recover the genetic material of the microbes that were preserved and frozen 1000 years ago or 500 years ago, in the way that we can somehow reconstruct or build the genetic story of the microbes from the past, for example, pre-industrial revolution to present. We need to think that microbes sustain the rest of the food web. So, they sustain of the rest of life in the ocean. They provide carbon for the rest of organisms, the fishes, whales [and other] big animals that we have in our oceans. And if the microbes are responding in a way that is not satisfactory, or in the way that we think can maintain the food web, this is kind of scary. And this is what we are trying to do: we are trying to go back to the past and see how the microbes are changing [genetically]. Sample Collection We didn't collect the samples. [They were collected] back in the 90s, so, 40 years ago, by a German group led by the Alfred Wegener Institute, which is probably one of the most famous polar institutes in the world. They, basically, led an expedition, I think it was in 92, and they decided to go to this ice shelf in Antarctica, in the Filchner–Ronne Ice Shelf to collect these ice cores. And then the surprise was when they were progressing in the drilling, they realized that on the top part of the ice core was fresh water, meteoric snow that was compacted forming the ice. But they realized that below that part, there was a sea water that was frozen. And then they thought that these samples were very interesting, because they somehow store material from the past, and they shipped these samples to Alfred Werner Institute in Bremerhaven in Germany. And half of the samples were stored for 40 years until I decided to contact the Institute and to propose this research. And I basically contacted the director of the Institute, and also the group of Frank Wilhelm, to propose the idea. And basically, I ...
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    49 分
  • Revenge of the Microbes With Brenda Wilson and Brian Ho
    2025/01/16
    Episode Summary Mother-Son duo, Brenda Wilson, Ph.D., professor of microbiology and the Associate Director of Undergraduate Education in the School of Molecular and Cellular Biology at the University of Illinois at Urbana Champaign and Brian Ho, Ph.D., researcher and lecturer at the Institute of structural and molecular biology, a joint institute between the Department of structural and molecular biology at the University College of London and the Department of Biological Sciences at Birkbeck University of London discuss the inspiration and motivation for their recent book, Revenge of the Microbes: How Bacterial Resistance is Undermining the Antibiotic Miracle, 2nd Edition, emphasizing the global nature of AMR and providing a unique perspective on what is needed to solve it. Ashley's Biggest Takeaways: Dynamics surrounding the AMR crisis are complex and require an understanding of many different perspectives, including those of the farmers, health care professionals, pharmaceutical companies and individuals, in order to foster true and lasting global collaboration on the issue.Point-of-care diagnostics are critical to improving treatment decisions and reducing hospital costs.Better communication and education are needed in order to rebuild trust in scientists and institutions.Continuous research is necessary, as AMR will continue to evolve.Citizens are a key piece of the puzzle when it comes to pushing for change and supporting solutions to AMR. Featured Quotes: Wilson: "I'll start with actually my Ph.D., which is talking about bacterial antibiotic biosynthesis. And so, I did some work in that arena, but since then, I've actually been working on bacterial protein toxins. These are very potent eukaryotic modulators that when bacteria get into the host, they release these proteins that are very large, that are able to interact with very specific cells. They actually get inside the cells—into the cytosol—and then they affect various signaling pathways in the host that can go anywhere from killing the cell to modulating some of the processes that the cell undertakes, even differentiating them and causing cancer. So, one of my main focuses in my lab has always been to understand the structure and function of these toxins, to understand how they affect the eukaryotic cell system. And then now that we know a lot about them, we're actually moving more into the direction of trying to basically use them as biologics. We have some platforms that we call bacterial toxin inspired drug delivery, where we're using the mechanisms of how they work and their exquisite specificities to be able to actually use them for therapeutic applications." Ho: "I got my start doing molecular genetics, actually, with John Mekalanos at Harvard, and I was kind of at the ground floor of the seminal work looking at the Type VI secretion system. And so, I got a front row seat to the kind of discovery and a lot of the initial understanding of the system. And I've kind of taken that work and expanded beyond it to look at kind of the ways different bacteria interact with each other within microbial communities. So my current work is looking at both DNA conjugation as well as the type six antagonism, and how the bacterial interactions kind of work together to build a larger population dynamics and interface with like the hosts that kind of house a your microbial communities." Antimicrobial Resistance Wilson: "In 2005 [when the first edition of Revenge of the Microbes was written], there was very little activity or understanding about antibiotic resistance and how important it was. Outside of the field, doctors were encountering it. But oftentimes what was happening is they just said, 'Oh, well, we'll just find another drug, you know.' And pharmaceutical companies, they were recognizing that there was a problem, and they would go off trying to hunt for new ones. And then right around the late 90s, there was a big impetus, because they thought, 'Oh, we, we have a miracle here, because we now do complete genomes. We can get out the comparative genomics and all the high throughput things, all the animations,' and that this would lead to many more new discoveries. And I think the pharmaceutical companies were very disappointed, and they started backing out of what they deemed a huge commitment. Two decades later, people already were starting to get aware, at least in the field, and even the industry and the physicians. People were getting aware, but I think that they were stumbling, because of their silos, in trying to get interactions with each other. And I think part of it was that they felt that, 'Oh, we can try to solve it ourselves.' And in reality, this is a problem that that is concerning everyone, and everyone is contributing to it. Everyone has to find a solution to help, and we need to have more synergy. There have to be more interactions, and we have to do this at a much more global scale. And so that was sort of what, what we ...
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    52 分