TWiV 664: TWiV is for the dogs

September 17, 2020

On this mid-week edition, does it matter that SARS-CoV-2 is mutating, seasonal coronavirus immunity is short-lived, another bogus claim that the virus was produced in a laboratory (it came from Nature), and answers to listener questions.

Hosts: Vincent Racaniello, Rich Condit, Kathy Spindler and Brianne Barker

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Download TWiV 664 (73 MB .mp3, 122 min)
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Links for this episode

  • Coronavirus is mutating (Nature) 9:29
  • Seasonal CoV immunity is short (Nat Med) 18:16
  • Sorry, no link to the fake science document! 40:44
  • Letters read on TWiV 664 1:08:02
  • Timestamps by Jolene. Thanks!

Intro music is by Ronald Jenkees

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16 comments on “TWiV 664: TWiV is for the dogs

  1. i liked your old podcasts Sep 17, 2020

    vincent will never bring a guest like Sorensen…
    he is not up to it.

  2. Norman Bauman Sep 17, 2020

    Here’s the virology entry in the Dance Your PhD contest last year. It describes how the bacteriophage HK97 uses small terminase and large terminase to package its DNA into a protein shell.

    This bridges the gap between the layman and expert understanding of viruses. Someday a dance will be part of the sub mission for a PhD.
    Dance your PhD 2019: Modelling a Viral Motor
    Jan 12, 2019

    Dance your PhD submission 2019 by Dorothy Hawkins, University of York, Department of Structural Biology.

    Viruses consist of a protein shell (the capsid) encasing genetic material (DNA or RNA). They are infectious agents which require a host cell to reproduce, and thus exist on the boundary between living and non-living. For my soundtrack I was interested to see how scientist and non-scientists would define a virus.

    The virus HK97 infects bacteria. Inside bacterial cells HK97 utilises the host machinery to build both the protein shell (represented here by a tree) and DNA (represented by a ribbon).

    In order to complete the synthesis of new viruses the DNA must be packaged into the protein shell. This is performed by the most powerful motor known to biology. It consists of two protein subunits: small terminase, played by the dancer in silver and large terminase shown by the dancer in red.

    Small terminase recognises a specific sequence on the DNA and recruits large terminase. Large terminase, in turn, latches onto the portal protein, which represents the door into the capsid, and is shown here by a metal hoop. Now the motor is fully assembled and large terminase, the powerhouse, can package DNA into the capsid. An enormous internal pressure is reached. Packaging stops when large terminase cuts the DNA at the next special sequence.

    The aim of my PhD is to build a 3D model of this motor using cryo-electron microscopy. Here, a beam of electrons is fired at the sample. Interactions between the electrons and sample produce 2D images of the sample in different orientations. These faint 2D projections are processed in groups in order to build a 3D model of the sample. This is represented by the development of a Polaroid photo.

    The packaging motor for HK97 strongly resembles that of the human Herpes viruses, where the large terminase represents a strong target for drug design.

  3. Viliame Finau Sep 17, 2020

    Hi Vincent,
    I live in Auckland, New Zealand and the government has implemented a new Covid-19 restriction level of 2.5. It is more freedom of movement compared to level 3, stay home order but slightly less freedom than level 2. Initially the nation was confused because this level is the result of political and a business pressure. On a personal level, I have a handful of extended family members who do not believe there is a pandemic. I have tried to encourage them to watch TWiv 664 by sharing the YouTube link on my family Facebook group page. Recently, a cousin of mine who is a strong anti-vax shared a video of a Dr. Li-Meng Yang, Chinese Virologist interview with Tucker Carlson. I found another and 31 minutes long interview with Jan Jekielek of The Epoch Times or American Thought Leaders. I already know you had debunked the theory but can you please do a session to counter this “Whistleblower”.
    I look forward to your next video

  4. Patricia Semken Sep 17, 2020

    Good morning to you all!

    A bright, mild day in London.

    Thought you might be interested in the above.

  5. Apparently, Prof Ralph Baric said in an interview to Italian journalists that it is totally possible that SARS-CoV-2 could be the fruit of genetic engineering in a Chinese laboratory.
    I do not have access to the original interview, but this is what newspapers are reporting.


  6. I hope Vincent carries through on his suggestion to make a video of the discussion of the bogus document. I’d like to have people hear this who shy away from listening to the whole two hours of TWIV

  7. Duncan Idaho Sep 17, 2020

    From Nature

    Papers are increasingly impenetrable
    From obscure acronyms to unnecessary jargon, research papers are getting harder to read – even for scientists. Statisticians analysed the use of acronyms in more than 24 million paper titles and 18 million abstracts and found that the use of acronyms is commonplace and on the rise. Of the roughly 1.1 million acronyms identified, the vast majority (79%) were used fewer than 10 times in the scientific literature. “Scientists love to write these acronyms,” says statistician Adrian Barnett, “but other scientists don’t necessarily pick them up, and they end up hanging around and causing a lot of confusion.”

  8. Donna Sep 17, 2020

    Can someone tell me if there has been a proven case of fomite acquired Corona virus?

  9. Technically labs also come from Nature too… Unless you think that bird nests are unnatural / lab created.

  10. JJackson Sep 19, 2020

    A couple of points for your consideration re. CoV immunity.
    As a fellow pedant I think we have eradicated more than one virus Smallpox and SARS-1.
    I remember Ralf and Stanley Perlman both seemed to think it may just become another cold like human CoV with limited pathogenicity and I understand the reasoning behind that but my concern is the high variance in the pathogenicity of the CoVs which we have had the opportunity to watch emerge. The zoonosis of the CoVs involved in common colds occurred so long ago we do not know how virulent they were originally and therefore the degree of attenuation that prior infection provides. Were they H1N1(2009) like or MERS like in terms’ of morbidity and mortality’?. My concern is we may end up with another endemic circulating pathogen, with or without marked seasonality, which still causes a severe flu like illness but with a raft of rather unpleasant sequelae.
    As a fellow pedant I think we have eradicated more than one virus. I would argue that SARS-1 was eradicated by human intervention and in earlier times would have gone global

  11. Jeffery J Biss Sep 19, 2020

    I’ll tell you why the fake document was produced, to destroy America’s political system such that China can take advantage of our inability to function as a world leader and move into that role.

    Not that the US is always a beneficent power, but that’s what they’re after.

  12. Richard Cornell Oct 5, 2020

    I once belong to “The Society of Motion Picture and Television Engineers”. For a meeting our host brought in a very well done movie about growing “string macaroni”. From planting the seeds in the right type of soil. To the amount of sunlight allow on the seed as it sprouted, and as the tree grew. As the flowers bloom to the string macaroni developed. After the lecture seed packets were given out with detail instructions.
    April 1 meeting.
    Seeing a 26 page paper on how to make a virus in a lab would have been on the level on playing a April Fool joke. Will people believe it. Yes. They believe in Gods do they not. Why not adding fake news to fake rumors.
    Past the glass of bleach I feel a little dry.