Dr. Kathryn Boor is a professor and chair in the Food Science department at Cornell University, where she’s director of the Food Safety Laboratory - a biosecurity level 2 laboratory that facilitates research on foodborne pathogens. Her particular research interests lie in the “how” and “why” of pathogens and spoilage microbes in food. Boor is also the director of the Milk Quality Improvement Program – a program funded by New York state to monitor and make recommendations to improve the quality of milk in the state.
When I think about the complicated way dairy products come to be on the shelf in my grocery store – farmers use machinery to extract milk from an animal that lives in a barn or a field; the milk is piped through long tubes to a tank on a truck that conveys the product to a plant that processes and divvies it up; the bottles and packages are put on another truck and carted to the store – it seems like a wonder dairy is ever safe to eat. But dairy is safe: CDC data indicate that less than 1% of foodborne illness outbreaks in the U.S. involve dairy products1 2 .
Dr. Boor’s primary interest lies in Listeria monocytogenes, one of the few pathogens that is a problem in dairy, and most people who’ve heard of it associate it with unpasteurized soft cheese or cold cuts. Listeriosis is not as common or familiar as some other foodborne illnesses, but it is more often fatal than salmonellosis or botulism, and in a pregnant woman even a mild case can be deadly for her fetus. Dr. Boor’s research focuses on how this so-called “simple” organism is able to persist in some foods and overcome the stress of refrigeration and stomach acid to not only survive, but to make us really sick.
In this interview, I asked Dr. Boor about how she came to this particular niche in science, whether pasteurization is any better than keeping milk from getting contaminated in the first place, and what her trained eye for food safety looks out for when she’s buying food.
1 U.S. Dept. of Health and Human Services, Public Health Service and Food and Drug Admin. 2003. Grade “A” Pasteurized Milk Ordinance. 2003 Revision.
2 Data are available at the Centers for Disease Control and Prevention’s website: http://www.cdc.gov/foodborneoutbreaks/outbreak_data.htm
Direct download: MTS15
Moselio Schaechter – known as Elio to his friends – is Distinguished Professor of Molecular Biology and Microbiology, Emeritus, at the Tufts University School of Medicine, and he’s currently an adjunct professor at San Diego State University and at the University of California at San Diego. Dr. Schaechter has had a long career in bacteriology and has authored or co-authored a number of text books, and is a former president of the American Society for Microbiology. He lives in sunny San Diego now, where he lectures, attends meetings, and writes his blog, “Small Things Considered”.
If you want an example of the ways the internet has changed public discourse, look to the blogs - you’re reading one now, after all, and how many blogs did you read 10 years ago? Blogs give authors a bullhorn free from profit-driven publishers, provide people with ideas, and even build communities through reader discourse. To be sure, not every blog is interesting or even readable, but there are many bloggers out there working hard and stimulating some profound discussions.
Those of us interested in the life microscopic are lucky to have Dr. Schaechter, who muses on the topics of interest to him and acts as host to other eminent scientists who write guest essays. With Small Things Considered, his goal is to express his own interest in various subjects while encouraging interest in others and kindling conversation and debate.
In my interview with Dr. Schaechter, we talk about what he gets out of being a blogger, what makes for a successful blog, and about how mushroom hunting in xeric Southern California usually involves a lot of hunting and few mushrooms.
Blogs and Websites mentioned in this episode include:
Direct download: MTS14
Joel Sussman, Ph.D. is a professor of structural biology at the Weizmann Institute of Science in Israel. In his research, Dr. Sussman is interested in elucidating the structures and functions of proteins, particularly those involved in the nervous system. He is also the lead scientist behind Proteopedia – a new online protein structure encyclopedia.
Scientific endeavors have historically been a one-way street: an investigator or lab makes a discovery, then delivers the good news to the rest of the community via publication. Nowadays, computers and the internet are enabling easier and more seamless means of collaboration and communication. Proteopedia, with which Dr. Sussman is greatly involved, automatically gathers and compiles information from multiple curated sources of information, but its more revolutionary side is the wiki tool, which enables registered users to contribute information themselves.
In this interview with Dr. Sussman, I talked with him about his work with acetylcholinesterase and “intrinsically unstructured proteins” and about Proteopedia – how it works and about the possibility of misinformation making its way onto the site.
The video below shows Proteopedia in action. It is narrated by Eran Hodis, the graduate student, who, together with Professors Jaime Prilusky & Joel L. Sussman developed Proteopedia at the Weizmann Institute of Science.
Direct download: MTS13
Nancy Keller is a Professor of Bacteriology and Medical Microbiology and Immunology at the University of Wisconsin-Madison. A mycologist, Dr. Keller works with a genus of fungi called Aspergillus – many of which are potent plant and human pathogens that produce deadly mycotoxins. Her research focuses on finding those aspects of Aspergillus species that make them effective as pathogens and toxin factories.
Tiny fungi cause big problems for agriculture and human health, and the U.S. alone spends millions of dollars every year to fight the fungi that attack crops. Aspergillus fungi, in particular, cause a problem for crop plants themselves, but the bigger concern is the mycotoxins they produce: aflatoxin is one of the most potent naturally-occurring toxins ever discovered. What’s more, aflatoxin and other Aspergillus toxins are carcinogenic. The bottom line? Exposure to large amounts of these fungal toxins can kill you quickly, and exposure to small amounts can kill you slowly.
On this episode, I talk with Dr. Keller about her work with Aspergillus, why we don’t even know how big the fungal toxin problem is, how reproduction and toxin-making are linked in these fungi, and how we may eventually use viruses as weapons against pathogenic fungi.
Direct download: MTS12
Daniel Lew is a professor of Pharmacology and Cancer Biology and of Genetics at the Duke University Medical Center in Durham, North Carolina. His research program focuses on cell cycle control in yeast, and how the cell cycle interacts with cell polarity.
Yeast cells may look simple, but inside every little single-cell package lurks an intricate creature that senses and responds cunningly to its surroundings. Dr. Lew has uncovered many of the secrets of the tiny yeast, and since yeast bear a striking resemblance to human cells, some of these facts could help us eventually conquer our own problems with the cell cycle, including cancer – a kind of cell division gone wild.
In this interview, I talk with Dr. Lew about how a yeast cell knows when to say “when” during budding, why he studies yeast at a medical school, and where his hard-to-discern accent really comes from (hint: it’s not a North Carolina accent).
Direct download: MTS11
Tony Maurelli is a professor of microbiology and immunology in the F. Edward Hébert School of Medicine at the Uniformed Services University of the Health Sciences in Bethesda, Maryland. Dr. Maurelli’s major research interest lies in the genetics of bacterial pathogenesis – the genetic nuts and bolts of how bacteria infect humans and make us sick.
Dr. Maurelli’s work has uncovered “antivirulence genes” in Shigella flexneri, a major cause of dysentery and food borne illness. This is an interesting concept: antivirulence genes undermine pathogenicity, so they must be broken or dropped from the genome for a bacterium to take good advantage of a host and cause disease. These genes are a hindrance, so to become an effective pathogen, Shigella must stop using them.
In this interview, I talked with Dr. Maurelli about antivirulence genes, about whether the naming system for bacteria should be fixed, and about his favorite bacteria.
Direct download: MTS10
Stanley Falkow is a professor of Microbiology & Immunology at the Stanford School of Medicine. His research interests lie in bacterial pathogenesis – how bacteria cause infection and disease – and over the course of his career he has contributed fundamental discoveries to the field. Falkow received the Lasker prize this year for special achievement in medical science, and the Lasker Foundation calls him “one of the great microbe hunters of all time”.
Molecular techniques (methods of analysis that rely on bacterial DNA) are now widely used for infectious disease diagnosis, thanks in large part to Falkow, who was among the first to apply an understanding of genes and virulence determinants to analyzing patient samples. He has published extensively in areas ranging from antibiotic resistance to food borne illness to microarrays. It is really difficult to compose interview questions for a scientist whose career has been as far-reaching and profoundly significant as Stan Falkow’s. Luckily for me, Dr. Falkow is a gracious conversationalist.
In this interview, I talked with Dr. Falkow about his prescient concerns about the dangers of using antibiotics as growth promoters in livestock, why Salmonella is so good at making you sick, and why students who are interested in science should follow their passion.
Direct download: MTS9
Rachel Whitaker is an assistant professor of microbiology at the University of Illinois at Urbana-Champaign, where she has developed a research program focused on the evolutionary ecology of microorganisms. Much of Dr. Whitaker’s work centers around a hyperthermophile found in geothermal springs: the archaeon Sulfolobus islandicus.
Evolution is not just history – it’s still in action today, molding humans, plants, animals and, of course, microbes, in ways we still don’t completely understand. One of Whitaker’s focus areas is archaea, a group of single-celled microbes that are found in some of the harshest environments on earth. By looking at how one variety of archaea, Sulfolobus, varies from place to place, Whitaker hopes to find whether Sulfolobus is adapting new characteristics to suit its habitats, and whether this kind of adaptation can help us explain why there are so many different kinds of microbes in the world.
In this interview, I asked Dr. Whitaker about the hot springs where she studies Sulfolobus, whether it’s hard to communicate with ecologists who work with bigger organisms, and about new discoveries she’s made related to an immune system in archaea.
Direct download: MTS8
Dr. Anthony Fauci is the director of NIAID – the National Institutes for Allergy and Infectious Disease – where he is also Chief of the Laboratory of Immunoregulation. Dr. Fauci’s research interests lie primarily in the molecular mechanisms of HIV and AIDS, and he has published extensively on the interactions of HIV with the immune system. He’ll be speaking at the opening session of ICAAC – the Interscience Conference on Antimicrobial Agents and Chemotherapy – on October 25 in Washington DC, where he’ll describe some of the remaining challenges in the fight against HIV, tuberculosis, and antibiotic resistant microbes.
Dr. Fauci is not only a researcher, he is also an important player in science policy in the U.S. He was a primary architect of PEPFAR, the President’s Emergency Plan for AIDS Relief, a program that received reauthorization and has a budget of $48 billion for HIV/AIDS, tuberculosis, and malaria around the world. In honor of his efforts to improve our understanding and treatment of HIV and AIDS, Dr. Fauci was recently awarded the Presidential Medal of Freedom, the nation’s highest civil award.
In this interview, I talked with Dr. Fauci about progress in managing infectious disease on a global scale, why it’s the “devil you don’t know” that is still the scariest infectious disease of all, and about the roles of abstinence education and condom awareness in PEPFAR.
Direct download: MTS7
Bruce Rittmann, the Director of the Center for Environmental Biotechnology at the Biodesign Institute of Arizona State, focuses his efforts on reclaiming contaminated water and producing renewable energy using microbes.
He was elected to the National Academy of Engineering in 2004 and credited with pioneering development of biofilm fundamentals and contributing to their widespread use in the bioremediation of contaminated ecosystems. His research combines many disciplines of science, including engineering, microbiology, biochemistry, geochemistry and microbial ecology. Formerly with Northwestern University, Rittmann is also a leader in the development of the Membrane Biofilm Reactor, an approach that uses bacteria to destroy pollutants in water. The Membrane Biofilm Reactor is especially effective for removing perchlorate from drinking water, and it is being launched commercially.
In this podcast, I talk with Dr. Rittmann about the biofilm reactor process, the electricity hiding in our wastewater, and how we may some day grow fuel on the roofs of buildings.
Direct download: MTS6