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TWiM regularly receives listener email with corrections, comments, suggestions for show topics, requests for clarification, and additional information. A selection of these is archived on this page.
Vincent, TWIV, TWIP amd TWIM are wonderful for a retired person like myself. I worked in IT, but started out with a biology undergrad that instilled my interest in biology many years ago. I always look forward to the next podcast. I have discovered that dinner conversation about TWIP is not as well received as a discussion about my latest project from the course I am taking at the College of Craft and Design. You will enjoy this
Hello, I am a big fan of all your podcasts. Copper is used as an anti- parasite agent in marine aquariums. It is toxic to all invertebrates and is deadly to them so it is used in fish only quarantines. This is perhaps why there is a concern about copper in the marine environments as it will not only kill microbes but snails, crabs, squid ect.
Hey guys, love your show so far. I have a few thoughts on the last episode concerning B. anthracis, particularly the lack of variance in anthracis. I found it very interesting to learn that spore-forming species have characteristically more genetic variance than non-spore formers. Does the lack of genetic variance have something to do with the fact that anthracis forms endospores, and not spores in a fungal sense? Fungal spores are easily released into the air for dissemination, while anthracis endospores seem fit to persist in the soil and dead bodies of infected animals. Do fungal spores show more genetic variation in a strategy to survive in a more diverse environment? Maybe Bacillus anthracis spores are less inclined to disseminate throughout the environment because the cattle and sheep they typically infect die within a few days and are generally confined to the field of the farmer who owns them.
Thanks, keep up the great work!
Hello Professors and Expert,
I am hoping for an upcoming episode on resistant bacteria or upcoming antibiotic drugs in the pipeline?
Your fellow cytogenetics friend,
Northwestern Memorial Hospital
I love this new podcast, and I especially enjoyed this episode. This is a nice example of both the strength and weaknesses of scientific forensic evidence, I think--you can get useful information out of it (the anthrax strains in Ivins' lab are very likely the source of the anthrax used in the attacks), but not the critical questions you care about (was it Ivins who made the spores and mailed them, or was it someone else; if it was Ivins, did he have any help?) I suppose we will never really know for sure, since Ivins is dead and the FBI's investigation is over.
Assuming Ivins was the attacker, this raises an interesting point with respect to the threat of bioterrorism: Ivins was a US government biological weapons researcher, working on defending against a potential attack. He had expertise, equipment, training, supplies, and access to information at a level that it's hard to imagine any other terrorist having. And yet, his total body count Online Pokies was quite small, as these things go. Some nut with a gun in a crowded mall might manage to kill about that many people! The attacks were quite effective at spreading terror, especially among people at the top of government and media, but they weren't actually all that deadly.
My question is, does this suggest that bioterrorism is overblown as a threat? Or is it just that this attack wasn't targeted at killing large numbers of people, or that we got lucky and things might have ended up far worse? My understanding is that anthrax isn't really much of a risk to spread after it has been used, and once you know people have been exposed you can give them antibiotics that will save them, so the attacks were probably self-limiting. Maybe the situation would have been different, had the attacker had access to a different agent?
This link, http://www.thermus.org/e_index.htm , is a good source of information about Japanese activities, has links to seminars, abstracts, software information that's being used, project background, 3D visualizations and progress reports, all in English. Might be of interest to listeners who wish to see what is going on in East.
There is an effort underway to ban Triclosan and I would like to hear TWIM discuss the risk / benefit to using anti-bacterial agents, particularly their widespread use in consumer products. Any info on how useful Triclosan is whether we'd miss it if was banned would be appreciated.
Kerry (Loyal laymen listener toTWIV, TWIP and now TWIM)
I just wanted to comment on your short discussion of nomenclature for Salmonella. Panama is not a serovar of enteriditis. Salmonella is currently recognized as having two distinct species, Salmonella enterica and Salmonella bongori. Salmonella enterica has 6 subspecies, of which subspecies enterica is the most clinically relevant. Within Salmonella enterica subspecies enterica, there are many serovars, of which Panama is a representative. Enteriditis is also a serovar of Salmonella enterica subsp. enterica. Therefore the proper name for this outbreak strain would be Salmonella enterica subspecies enterica serovar Panama. Whenever Salmonella Panama is used, or Salmonella Enteriditis, it implies that the serovar is a member of the enterica subspecies enterica family.
Vincent and everyone else on TWiM, I have throughly enjoyed these podcasts, they are perfect entertainment while I am stuck spinning down large culture volumes. I especially enjoy the format, focusing on just a few papers/topics really allows for in depth discussion.
Please continue your coverage on all the human microbiome work, it is a fascinating topic. As a undergrad at Cornell I was lucky enough to take the first offering of a course devoted solely to our microbiota, especially its positive impact. The course sold me on the importance of this field and its potential to change the way we look at some of the most important diseases that afflict us today.
Also, I am looking forward to your coverage of bacteriophages and phage related therapy, especially the future of its use in medicine.
The matriarch of a hunter-gatherer band might prefer males to be assigned to specialised training in hunting skills. So the subconscious bias probably goes back a couple of million years to the early days of Homo before sapiens.
Saw this paper in my inbox this morning and thought It might be a good fun discussion paper on an upcoming TWiM episode!
Dear Dr Racaniello,
I do not have the talent for a M.D-Ph.D. at Columbia, but I am madonna pokies definitely a huge fan:)
It's striking how and where the interaction of antibody and bacterium occurs (TWIM #48)! Learned a lot from listening to your interpretation of the paper. Many Thanks!
Just have a question about one antibody and one bacterium. Is it commonly considered more than one antibody molecule per bacterium?
Many Thanks, again!
P.S. Can this finding extent to the interaction between virus (e.g. HIV) and neutralizing antibody? It might be we just look at the wrong place for all those years!
Hello Racaniello et al.,
I am a plant pathologist for a vegetable seed company in Washington state. I listen to TWIM, TWIP and TWIV podcast while I read extensive disease resistance screens. I started out studying microbiology as an undergrad and discovered plant pathology that allows me to study microbes and plants together. Listening to these podcasts keeps my mind engaged while looking at thousands of potentially disease baby plants. I really appreciate what you all do to put together such intellectually stimulating topics.
If I may suggest a topic as well. Iron sequestration and uptake in bacteria is very fascinating and affects many aspects of bacterial life. I may be biased as I worked on iron uptake during my Ph.D. I have listened to many of the TWIM podcasts and iron pops up in discussion now and then. It would be nice to listen to a discussion of this topic from your perspective.
Keep up the good work,
Episode 2 had a career inquiry from a listener. The listener was considering additional graduate work Pokies, but was not sure which way to go or whether to invest the required time and energy in an MBA or Ph.D.
May I suggest intellectual property as a career path? Most patent attorneys are former "lab rats." Patent attorneys enjoy a good salary and interaction with some very intelligent and interesting people. Though considerable work is required, intellectual property can be a very rewarding career.
Quick follow-up from Twim 47.
It seems that many bacteria have means to take up foreign DNA and integrate it Into their own chromosomes. This definitely can provide a selective advantage depending on the nucleic acids being taken up. On the other hand, transferring your own DNA to another cell seems to be quite unselfish. For example, if I had some form of an antibiotic resistance gene, why would I give it away to others that would, in the end, compete with me for nutrients? In essence, what is the selective advantage for giving away nucleic acids?
Thanks a lot and have a happy holiday!
I love all your series (TWIM,TWIV, and TWIP) and learn immensely from them. I am a Clinical Research Nurse and work at NIH in the National Institute of Allergy and Infectious Disease (NIAID) unit that houses the KPCR patients that you may have recently read about.
I'd like to hear a discussion about this isolate as you educate everyone so thoroughly. Our hospital has worked diligently to track and eliminate this organism from our hospital and we've just about succeeded but I'd still like to be better informed about KPCR. Thanks.
P.S. Please Please Please start a TWIB!! We work with so much that I still need to be educated about various bacteria.
Thanks immensely for all the education you give us.
Hi Vincent and Friends,
Thank you very much for the informative and often imaginative discussions that take place in TWiM. It's a real pleasure to listen to such a quality, fun, easily accessible (and free!) source of microbial material. I'm sure you are often thanked for taking the effort to put it out there, but I wanted to add my voice. As a cell and molecular biology student it offers some wonderful connections and points of interest to my education.
My question relates to a recently published book by Trudy M. Wassenaar that I have been reading, titled "Bacteria: The Benign, the Bad, and the Beautiful." Has anyone read this book, and if so what are their thoughts on it? I would recommend it to those with a broad interest, or who need an introduction, like students such Pokies as myself. It offers an incredibly interesting and diverse description of bacteria and is easy to understand. I actually picked it up because it was recommended by the google+ "Microbiology" account (https://plus.google.com/u/0/109102265263486263584/posts).
Thanks again, and warm regards.
TWiM Audio File with Interactive Transcription
Here is a link to a partial, video I created from the TWiM 06 audio file: http://www.youtube.com/watch?v=JtOXD_X6g_w. I created a video file from the audio file so that I could use the YouTube captioning tool to import an interactive transcript -- minutes five (5) through twelve (12). I created the time-coded transcript using an online tool called Subtitle-Horse, (http://subtitle-horse.com).
If you click the interactive transcript button on the button-bar (Like, Dislike, Add to, etc) just below the video player, you can see how the transcript works. The transcript is indexed, time coded to the audio.
Potential Benefit of Interactive Transcription
The time-coded transcript text could be parsed and placed in a database for easy query. Then all included audio/video files are text searchable and associated to the segment of the source audio/video clip.
On TWiV a number of people have completed or are working on transcripts. In my experience, transcription is a time intensive process. To lighten individual time commitment, it would be nice to get several people to work collaboratively to transcribe one TWiV audio/video. Although far from perfect, the subtitle-horse online transcription tool could be used for this.
Volunteer to Help TranscribeAs a first step, if interested, I’d be interested in coordinating a collaborative transcription of a TWiV session with one to three others.
Hello TWIMers - In TWIM 26 I heard the listener email asking if you would consider offering continuing education credit for your podcasts, and you understandably cited the work that would you need to do (such as writing learning objectives, tests etc) as a real barrier to that. I was wondering if you would consider "contracting" that kind of work out to some of your listeners; being a teacher of a microbiology class at a community college, I spend a large amount of time coming up with learning objectives, tests etc anyhow, and it would help me to generate fresh material for my students from your podcasts. I wouldn't be surprised if there were others in your listening base who might feel the same. This still would add work for you, so I understand if its a no-go.
In a separate vein: quite a while ago I was doing dishes and listening to a TWIM. As I was using a sponge to wipe off the counter a ridiculous question popped into my head (as opposed to my toe, I guess): are there strains of bacteria that can provide a protective commensal role on environmental surfaces? A counter top is nothing like a biological surface, as only the latter should have organic material to eat on it, but still, is there any evidence in any situation that something like this happens? Please read the following sentence with extra emphasis: I am not fishing for an excuse to get out of doing the dishes, and I regularly boil our kitchen sponges and use bleach to Pokies clean the counters.
Keep up the great work!
Greetings from a longtime listener and fan of all three TWI-podcasts. I'm a biotechnology Masters student at the University of Helsinki, Finland, but I earn my living as a part-time driver in the world's most northern metro. Your podcasts help me pass the dull hours at work so that I feel like I'm doing something to advance my studies as well.
I've been thinking of writing for quite a while. Now that I'm finally doing it, I have a rather general suggestion and a link. The suggestion is, I'd like to hear more about the archaea - maybe even an entire episode dedicated to them. They seem like such a mystery. At least at my home university, they're almost always just mentioned as an aside, while the bacteria get all the attention. The one time they were actually discussed on a course, I learned that they are not just extremophiles, but actually all around us, just like bacteria. This made the fact that there are no pathogenic archeae seem even more curious to me.
As for the link, it's for the Earth Microbiome Project: http://www.earthmicrobiome.org/
I just ran across it today, and don't remember this project being mentioned on TWIM before. I think the idea is awesome, not to mention really ambitious, maybe even overly so. What do you think, is creating even a rough map of the microbiome of our entire planet an attainable goal? And would it be a useful resource for research?
Thanks for the inspiring and informative podcasts,
Dear TWiM Team,
I just finished listening to the TWiM 35 on LPS in Vibrio (among other topics). Dr. Elio Schaechter mentioned a field in Microbiology that I think is of great interest to the scientific community and should definitely be covered in a podcast. The topic is: Outer Membrane Biogenesis in Gram-negative bacteria. For decades people have been hypothesizing and trying to find an evolutionary link that would answer the following questions: how did a second membrane in bacteria come about and was the last universal common ancestor (LUCA) a single or double-membraned organism. These questions are extremely difficult to address and rely heavily on bioinformatics and phylogenetic analysis.
I'm the first author of the paper that I'm suggesting here as a resource for a potential podcast. I've read extensive amounts of scientific literature before the paper was finalized and published in Cell to realize that currently, there are no favored hypotheses and the very few hypotheses that exist are highly controversial. In our paper we structurally characterize (using electron cryo-tomography) the process of endospore formation. The process is typically thought of as exclusive to Gram-positive bacteria members of the phylum Firmicutes, however, we imaged a Gram-negative organism (Acetonema longum) that is also able to sporulate! Through our structural studies, phylogenetic profiling and biochemical analysis we showed that A. longum possesses a true outer membrane. Not only that, after sporulation, the spore is surrounded by two membranes both of which originated from the inner membrane of the mother cell. Upon outgrowth, the second membrane of the spore becomes the outer membrane of the bacterium and therefore is remodeled from and inner into and outer membrane. These are fascinating new results that may provide us with a missing link between Gram-positive and Gram-negative bacteria and give insights into how an outer membrane may have evolved.
Here are a couple of links to the paper I'm suggesting and a commentary by Dr. W. Vollmer on this work:
Dear Prof. Schmidt, I listened the podcast in Microbiology that you recently contributed together with Vincent Racaniello, Joseph John and Elio Schaechter. You made a very nice summary and commentary of the International Symposium on Staphylococci held last August in Lyon.
Furthermore, I would like to thank you for all your nice words about the symposium that we organized and on our recent opinion paper titled “Inferring reasons for the failure of S. aureus vaccines in clinical trials” and published in Frontiers Cell. Inf. Microbio.
Fabio Bagnoli, PhD
Novartis Vaccines & Diagnostics
Hey TWIM-MERs -- this is from a wildlife rehab newsletter, thought you might be interested:
MRSA in Wildlife
One of the most notorious and hard-to-treat bacteria in humans has been found in wildlife, according to a new study in the Journal of Wildlife Diseases. Researchers isolated methicillin-resistant Staphylococcus aureus (MRSA) in two rabbits and a shorebird. Wild animals may act as an environmental reservoir for the disease from which humans could get infected.
Molecular typing of the isolates showed that the shorebird carried a hospital-associated strain of MRSA, while the rabbits had community-associated strains. The rabbits' MRSA also was resistant to tetracycline, which is common in farm animals.
Perhaps most troubling of all was that one of the pigeons carried a Staphylococcus bacterium that, while still sensitive to methicillin, was resistant to the antibiotic vancomycin. "Vancomycin is used as a last resort in MRSA infections," says study co-author Shylo Wardyn, “and vancomycin-resistant staph strains are rare in humans.” Abstract: http://www.jwildlifedis.org/content/48/4/1069.abstractlink
Happy Halloween greetings Twim Team.
For a slightly microbiology themed Halloween costume I constructed a Plague Doctor mask.
You can see its construction on the instructables site:
Comment: I feel like this issue is quite broad and interesting and was hoping that ocean geoengineering might be worth discussing. It's my understanding that scientists are wary of such approaches, to say the least, but this event seems to demonstrate a certain necessity for the international community to come to terms with geoengineering and sort out strategies and methods. As a layman, I'd be very interested in what you guys have to say!
Quick excerpt from the beginning of the article:
"A controversial American businessman dumped around 100 tonnes of iron sulphate into the Pacific Ocean as part of a geoengineering scheme off the west coast of Canada in July, a Guardian investigation can reveal.
Satellite images appear to confirm the claim by Californian Russ George that the iron has spawned an artificial plankton bloom as large as 10,000 square kilometres. The intention is for the plankton to absorb carbon dioxide and then sink to the ocean bed – a geoengineering technique known as ocean fertilisation that he hopes will net lucrative carbon credits.
George is the former chief executive of Planktos Inc, whose previous failed efforts to conduct large-scale commercial dumps near the Galapagos and Canary Islands led to his vessels being barred from ports by the Spanish and Ecuadorean governments. The US Environmental Protection Agency warned him that flying a US flag for his Galapagos project would violate US laws, and his activities are credited in part to the passing of international moratoria at the United Nations limiting ocean fertilisation experiments
Scientists are debating whether iron fertilisation can lock carbon into the deep ocean over the long term, and have raised concerns that it can irreparably harm ocean ecosystems, produce toxic tides and lifeless waters, and worsen ocean acidification and global warming."
Thank you for the great podcasts,
I just found the latest edition of Clinical Microbiology and Infection and read about a concept that is new to me: culturomics.
Maybe you'll be as intrigued as me by this concept. It contrasts well wil all the high-throughput-genomics hype these days. It might be a good article to put on the show (some day?).
Here are the links, I am happy to forward pdf's of the articles to you if needed.
Culturomics: a new approach to study the human microbiome
Microbial culturomics: paradigm shift in the human gut microbiome study
And again, thank you for three great show to walk, commute, run, bike and do housework to:)
All the best,
Registrar in clinical microbiology
Vestfold municipal hospital, TønsbergNorway