Dmitry Korkin: Computational Biology of Coronavirus | Lex Fridman Podcast #90
CwyOUS8TSl0 • 2020-04-22
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Kind: captions Language: en the following is a conversation with Dimitri korkin he's a professor of bioinformatics and computational biology at WPI Worcester Polytechnic Institute where he specializes in bioinformatics of complex diseases computational genomics systems biology and biomedical data analytics I came across Dimitri's work one in February his group used the viral genome of the Cova 19 to reconstruct the 3d structure of its major viral proteins and their interaction with the human proteins in effect creating a structural genomics map of the corona virus and making this data open and available to researchers everywhere we talked about the biology of covert 19 SARS and viruses in general and how computational methods can help us understand their structure and function in order to develop antiviral drugs and vaccines this conversation was recorded recently in the time of the corona virus pandemic for everyone feeling the medical psychological and financial burden of this crisis I'm sending love your way stay strong we're in this together we'll beat this thing this is the artificial intelligence podcast if you enjoy it subscribe on YouTube review it with five stars in a podcast supported on patreon or simply connect with me on Twitter Alex Friedman spelled Fri DM a.m. this show is presented by cash app the number-one finance app in the App Store when you get it you just called Lex podcast cash app lets you send money to friends buy Bitcoin and invest in the stock market with as little as $1 since cash app allows you to buy Bitcoin let me mention that cryptocurrency in the context of the history of money is fascinating I recommend a cent of money as a great book on this history debits and credits on Ledger's started around 30,000 years ago the US dollar created over two hundred years ago and Bitcoin the first decentralized cryptocurrency released just over ten years ago so given that history cryptocurrency is still very much in his early days of development but it's still aiming to and just my redefined the nature of money so again if you get cash out from the App Store Google Play and use the code let's podcast you get ten dollars in cash app will also donate ten dollars the first an organization that is helping to advance robotics and STEM education for young people around the world and now here's my conversation with Demetri korkin do you find viruses terrifying or fascinating when I think about viruses I think about them I mean I imagine them as those villains that do their work so perfectly well that's that is impossible not to be fascinated with them so what do you imagine when you think about a virus do you imagine the individual so these hundred nanometer particle things or do you imagine the whole pandemic like Society level the when you say the efficiency at which they do their work do you think of viruses as the millions that him and that occupy human body or a living organism Society level like spreading as a pandemic or do you think of the individual little guy yes this is I think this is a unique a unique concept that allows you to move from micro scale to the macro scale all right so the dividers itself I mean it's it's not a living organism it's a machine to me it's a machine but it is perfected to the way that it essentially has a limited number of functions it needs to do necessary some functions and essentially has enough information just to do those functions as well as the ability to modify itself so you know it's it's a machine it's an intelligent machine so yeah look maybe on that point you're in danger of reducing the power of this thing by calling it a machine right but you now mention that it's also possibly intelligent it seems that there's these elements of brilliance that a virus has of intelligence of maximizing so many things about its behavior in to ensure its survival and its and its success so do you see it as intelligent so you know I think the it's a different understanding differently than you know I think about you know intelligence over human kind or intelligence of of the of the you know of the artificial intelligence mechanisms I think the intelligence of a virus is in its simplicity the ability to do so much with so little material and information but also I think it's it's interesting it keeps me thinking you know it gives me wondering whether or not it's also the an example of the basic swarm intelligence where you know essentially the viruses act as the whole and extremely efficient in that so what do you attribute the incredible simplicity and the efficiency - is it the evolutionary process - maybe another way to ask that if you look at the next hundred years are you more worried about the natural pandemics or the engineered pandemics so how hard is it to build a virus yes it's it's a very very interesting question because obviously there is a lot of conversations about the you know whether we are capable of engineering a you know anyone worse the virus I personally expect in a mostly concerned with the naturally occurring viruses simply because we keep seeing that we keep seeing new strains of influenza emerging some of them becoming pandemic we keep seeing new strains of coronaviruses emerging this is a natural process and I think this is why it's so powerful you know if you ask me you know did I've read papers about scientists trying to study the capacity of the modern you know by technology to alter the viruses but I hope that that you know it in it won't be our main concern in the near future do you mean by hope well you know if you look back and look at the history of the of the most dangerous viruses right so that's the first thing that comes into mind is a smallpox so right now there is perhaps a handful of places where this you know the the strains of this virus are stored right so this is essentially the effort of the whole society to limit the access to those viruses I mean in a lab in a controlled environment in order to study and then smallpox is one of the viruses for which should be stated there's a vaccine is developed yes yes and that's you know it's until seventies it wasn't in my opinion it was perhaps the most dangerous think that was there is there a very different virus then then the influenza and coronaviruses it is it is different in several aspects biologically it's a so-called double-stranded DNA virus but also in the way that it is much more contagious so they are not for so this is this is the what are not are not is essentially an average number as person infected by the virus can spread to other people so then the average number of people that he or she can spread it to and you know the there is still some you know discussion about the estimates of the current virus you know the estimations vary between you know one point five and three in case of smallpox it was five to seven and we're talking about the exponential growth right so that's that's a very big difference it's not the most contagious one measles for example it's I think 15 and up so so it's it's you know but it's definitely definitely more contagious that that the seasonal flu then the current coronavirus were stars for that matter so what makes a what makes a virus more contagious or the I'm sure there's a lot of variables that come into play but is it is it that whole discussion of aerosol and like the size of droplets if if it's airborne or there's some other stuff that's more biology centered I mean there are a lot of components and and there are biological components that there are also you know social components the ability of the virus to you know the the ways in which the virus is spread is definitely one the ability to virus to stay on the surfaces to survive the ability of the virus to replicate fast also you know once it's in the cell or whatever once it's inside the host and interesting enough something that I think we didn't pay that much attention to is the incubation period the were you know hosts are symptomatic and now it turns out that another thing that we one really needs to take into account the percentage of the asymptomatic population because those people still shared this virus and still are you know they still are contagious as other than the Iceland study which i think is probably the most impressive size-wise shows 50 percent asymptomatic this virus I also recently learned the swine flu is like just a number of people who got infected was in the billions it was some crazy number it was like it was like like 20 percent of poverty percent of population something crazy like that so the lucky thing there is the fatality rate is low but the fact that a virus can just take over an entire population so quickly it's terrifying I think I mean this is you know that's perhaps my favorite example of a butterfly effect because it's really I mean it's it's even tinier they'd then a butterfly and look at you know and with you know if you think about it right so it used to be in in those bad species and perhaps because of you know a couple of small changes in in the in the viral genome his first had you know become capable of jumping from bats to human and then it became capable of jumping from human to human alright so this is this is I mean it's not even the size of a virus it's the size of several you know several atoms or says you know few atoms and our sudden this change has such a major impact so is that a mutation like on a single virus is that like so if we talk about those the the flap of a butterfly wing like what's the first flap well I think this is the the the mutations that make that made this virus capable of jumping from bat species to human and of course there's you know the scientists are still trying to find I mean they still even trying to find the the who was the first in fact it is the patient zero the first human the first human infected right I mean the fact that there are corona viruses different strains of corona viruses in various bat species I mean we know that so so we you know viola gist absurdum they studied them they look at their and genomic sequences they're trying of course to understand what make this virus is to jump from from bats to human there was you know similar to that and in you know in influenza that was I think a few years ago there was this you know interesting story where several groups of scientists studying influenza virus essentially you know made experiments to show that this virus can jump from one species to another you know by changing I think just a couple of residues and and and of course it was very controversial I think there was a moratorium on this study for a while but then the study was released it was published so that was their moratorium is because it shows through engineering it through modifying it you can make a jump yes yeah I I personally think it is important to study this I mean we should be inform to should try to understand as much as possible in order to prevent it but so then the engineering aspect there is can't you then just start searching because there's so many strands of viruses out there can't you just search for the ones in bats that are the deadliest from the virologist perspective and then just try to engineer try to see how to but see that's a there's a nice aspect to it the really nice thing about engineering viruses it has the same problems nuclear weapons is it's hard for it to not only to mutual self-destruction so you can't control a virus it can't be used as a weapon right yeah that's why I you know in the beginning I said you know I I'm hopeful because that definitely the definitely regulations to be needed to be introduced and I mean as the scientific society is we are in charge of you know making the right actions making the right decisions but I think we we will benefit tremendously by understanding the mechanisms by which the virus can jump by which the virus can become more you know more more dangerous to humans because all this answers with you know eventually to to designing better vaccines hopefully Universal vaccines right and that would be a triumph of the you know science so what's the universe of vaccines is that something that well how universal is universal well I mean you know so what's the dream I guess because you kind of mentioned the dream of this I would be extremely happy if you know we designed the vaccine that is able I mean I'll give you an example right so so every year we do a seasonal flu shot the reason we do it is because you know we are in the arms race you know our vaccines are in the arms race with with constantly changing virus right now if the neck's pandemic influenza pandemic will a cure most likely this vaccine would not save us right although it's it's you know it's the same virus might be different strain so if we're able to essentially design a vaccine against you know influenza A virus no matter what's the strain no matter which species did jump from that would be I think that would be a huge huge progress and advancement you mentioned the smallpox until the seventies might have been something that he would be worried the most about what about these days well we're sitting here in the middle of a cove in nineteen pandemic but these days nevertheless what is your biggest worry virus wise what are you keeping your eye are on it looks like and you know based on the past several years of the of the new viruses emerging I think we're still dealing with different types of influence I mean so so the eight seven and nine avian flu that was that emerged I think a couple of years ago in China I think the the mortality rate was incredible I mean it was you know I think above thirty percent you know so this is this is fuchsia I mean luckily for us this strain was not pandemic alright so it was jumping from birds to human but I don't think it it it was actually transmittable between the humans and you know this is actually a very interesting question which scientists tried to understand right so the balance the delicate balance between the virus being very contagious right so efficient in spreading and virus to be very pathogenic you know causing you know harms you know and and that's to their horse so it looks like that the more pathogenic the viruses the less contagious it is is that a property biology or what is it was I I don't have an answer to that and III think this is this is still an open question but you know if you look at you know you know with the corona virus for example if you look at you know the the deadlier relative Merce Merce was never in a pandemic virus right but the you know did again the the mortality rate from nurseries far above you know I think twenty or thirty percent so so whatever is making this all happen doesn't want us dead because it's balancing yeah nicely I mean how do you explain that one not dead yet like because there's so many viruses and they're so good at what they do why do they keep us alive I mean we will also have you know a lot of protection right so the immune system and so I mean we do have you know ways to to fight against those viruses and I think with the I now weigh much better equipped right so with the discoveries of vaccines and you know there are vaccines against the the viruses that maybe two hundred years ago would wipe us out completely but because of this vaccines we are actually we're capable of eradicating pretty much fully as is the case with smallpox so if we could can we go to the basics a little bit of the biology of the virus how does the virus infect the body so I think there are some key steps that the virus needs to perform and of course the first one the viral particle needs to get attached to the host cell in the case of corona virus there is a lot of evidence that it actually interacts in the same way of the as the SARS coronavirus so it gets attached to a c2 human receptor and so there is I mean as we speak there is a growing number of papers suggesting it moreover a most recent I think most recent results suggest that this virus attaches more efficiently to this human receptor then SARS just a sore back off so there is a family viruses the corona viruses and SARS whatever the heck for that respite or wherever that stands for so SARS actually stands for the disease that you get is the syndrome of acute respiratory so SARS is the first strand and there's Merce Merce and there is yes but people scientists actually know more than three strains I mean so there is the mhv strain which is considered to be a canonical model disease model in mice and so there is a lot of work done on on this virus because it's but he hasn't jumped to humans yet no no yes it's fascinating so any mention a c2 so the when you say attached proteins are involved yeah on both sides yes so so we have you know so we have this infamous spike protein on the surface of the virion particle and does look like a spike and I mean that's essentially because of this protein you know we called the coronavirus coronavirus so that what makes Corona on top of the surface so so this via this protein it actually it acts so it doesn't act alone it actually it makes a three copies and it's it makes so-called trimer so this trimer is essentially a functional unit a single functional unit that in starts interacting with the AC two receptor so this is again another protein that now sits on the surface of a human cell host cell I would say and that's essentially in that way the virus anchors itself to the host cell because then it needs to actually it needs to get inside you know it fuses its membrane with the host membrane it releases the the key components it releases its you know RNA and then essentially hijacks the the machinery of the cell because none of the viruses that we know of have ribosome the the machinery that allows us to print out proteins so in order to print out proteins that are necessary for functioning of this virus it actually needs to hijack the host ribosomes the virus is an RNA wrapped in a bunch of proteins one of which is this functional mechanism with by protein that does the attachment so yeah so you know so if you look at this virus that there are you know several basic components right so we start with the Spike protein this is not the only surface protein the the protein that lives on the surface of the viral particle there is also perhaps the the protein with the highest number of copies is the membrane protein so it's essentially it forms the capsid sorry the envelope of the protein of the viral particle and essentially you know helps to maintain a certain curvature helps to make a certain curvature then there is a another protein called envelope protein or a protein and it it actually occurs in in far less quantities and still there is ongoing research what exactly does this protein do so these are sort of the three major surface proteins that you know make the divider envelope and when we go inside then we have another structural protein called nuclear protein and the the purpose of this protein is to protect the viral RNA it actually binds to the viral RNA creates a capsid and so the rest of the virus viral information is inside of this you know RNA and you know if you compare the amount of the genes or you know proteins that are made of these genes it's much you know it's significantly higher than of influenza virus for example influenza virus has I think around eight or nine proteins where this one has at least 29 Wow that has to do with the length of the RNA strand I mean so I mean so it's it it affects the length of the RNA strand right so so so because you essentially need to have sort of the minimum amount of information to encode those genes how many proteases you say 2909 protease yes so this is this is you know something definitely interesting because you know believe it or not we've been studying you know coronaviruses for over two decades we've yet to uncover all functionalities of his proteins could we maybe take a small tangent and can you can you say how one would try to figure out what a function of a particular protein is so you've mentioned people are still trying to figure out what the function of the envelope protein might be or what's the process so this is where the research that computational scientists do might be of help because you know in the past several decades was that we actually have collected a pretty decent amount of knowledge about different proteins in different viruses so what we can actually try to do and this is sort of could be sort of the our first lead to a possible function is to see whether those you know say we have this genome of the corona virus other of the novel coronavirus and we identify the potential proteins then in order to infer the function what we can do can actually see whether those proteins are similar to those ones that we already know okay in such a way we can you know for example clearly identified you know some critical components that RNA polymerase or different types of proteases these are the proteins that essentially clip the protein sequences and so this works in many cases however in some cases you have truly novel proteins and this is a much more difficult task now as a small pause when you say similar like what if some parts are different and some parts are similar like how do you disentangle that you know it's it's a big question of course you know what by informatics does it does predictions right so those predictions and they have to be validated by experiments functional or structural predictions both I mean we we do structural predictions with the functional predictions we do interactions predictions things you just generate a lot of predictions like reasonable predictions based on structure and function interaction like you said and then here you go that's the power of bioinformatics is data grounded good predictions of what should happen so we you know in the way I see it we're helping experimental scientists to streamline the discovery process yeah and the experimental scientists is that what a virologist is solely about virology is one of the experimental sciences that you know focus on viruses they often work with other experimental scientists for example the molecular imaging scientists right so the the viruses often can be viewed and reconstructed through electron microscopy techniques so but these are you know specialists that are not necessarily by biologists they've worked with small small particles more by whether it's viruses or is it an organelle of a you know of a human cell whether it's a you know complex molecular machinery so the techniques that are use are very similar in in surfing in its in their essence and so yeah so so typically me and in we see it now the research on you know that is emerging and that is needed often involves the collaborations between biologists you know biochemist you know people from from pharmaceutical sciences computational sciences so we have to work together so from my perspective is to step back sometimes I look at this stuff it's the how much we understand about RNA DNA how much we understand about protein like your work the amount of proteins that you're exploring is it surprising to you that we were able we descendants of apes were able to figure all of this out like how so your computer scientists so for me from computer science perspective I I know how to write a Python program things are clear but biology is a giant mess it feels like to me from an outsider's perspective is how surprising is it amazing is it that we were able to figure this stuff out you know if you look at the you know how computational science and computer science was evolving right I think it was just a matter of time that we would approach biology so so we we started from you know applications to much more fundamental systems physics you know and now we are or you know small chemical compounds right so now we are approaching the more complex biological systems and I think it's a natural evolution of you know of the computer science of mathematics sure that's the computer science I just might even in in higher level so that to me surprising that computer science can offer help in this messy world but I just mean it's incredible that the biologists and the chemists can figure all this out or is it you sound ridiculous to you that that of course they would it just seems like a very complicated set of problems like the the variety of the kinds of things that could be produced in the body the just just like you said 20 and I approach I mean just getting a hand of in a hang of it so quickly it just seems impossible to me I agree I mean it's and I have to say we are you know in the very very beginning of this journey I mean we we've yet to I mean we've yet to comprehend not even try to understand and figure out all the details but we've yet to comprehend the complexity of the cell we know that neuroscience is not even at the beginning of understanding human mind so where's biology said in terms of understanding the function deeply understanding the function of viruses and cells so there sometimes it's easy to say when you talk about function what you really refer to it's perhaps not a deep understanding but more of a understanding sufficient to be able to mess with it using a antiviral like mess with it chemically to prevent some of its function or do you understand the function well I think equally I think we're much farther in terms of understanding of the complex genetic disorders such as cancer where you have layers of complexity and we you know as in my laboratory we're trying to contribute to that research but we're also in a way overwhelmed with how many different layers of complexity different layers of mechanisms that can be hijacked by cancer simultaneously and so you know I think biology in the past 20 years again from the perspective of the outsider because I'm not a biologist but I think it has advanced tremendously and one thing that we're computational scientists and data scientists are now becoming very very helpful is in the fact it's kind of from the fact that we are now able to generate a lot of information about the cell whether it's next-generation sequencing or transcriptomics whether it's life imaging information where it is you know complex interactions between proteins or between proteins and small molecules such as drugs we we are becoming very efficient in generating this information and now the next step is to become equally efficient in processing this information and extracting the the key knowledge from that they could then be validated with the experiment yeah yeah so maybe then going all the way back we're talking you said the first step is seeing if we can match the new proteins you found in the virus against something we've seen before to figure out its function and then you also mentioned that but there could be cases where it's a totally new protein is there something biron firm addicts can offer when it's a totally new protein this is where many of the methods and you probably are aware of you know the the case of machine learning many of these methods rely on the previous knowledge right so things that where we try to do from scratch are incredibly difficult you know something that we call a Benicia and this is I mean it's not just the function I mean you know we've yet to have a robust method to predict the structures of these proteins in a Benicia you know by not using any templates of other related proteins so protein is a chain of amino acids residues as residues yeah and then however somehow magically maybe you can tell me they seem to fold in incredibly weird and complicated 3d shapes yes so and that's where actually the idea of protein folding or just not the idea but the problem of figuring out how the hell it wants up the concept how they fold into those weird shapes comes in so that's another side of computational work so what can you describe what protein folding from the computational side is and maybe your thoughts on the folding at home efforts that a lot of people know they you can use your machine to to do protein folding so yeah broad protein folding is you know one of that those 1 million dollar price challenges right so the reason for that is we've yet to understand precisely how the protein gets folded so efficiently to the point that in many cases where you you know where you try to unfold it due to the high temperature it actually folds back into its original state right so we know a lot about the mechanisms right but put putting those mechanisms together and making sense it's a computationally very expensive task in general the proteins fold can they fold in arbitrary large number of ways it is they usually fold in a very small number no it's it's typically I mean you we tend to think that you know there is a one sort of canonical fold for protein although that there are many cases where the proteins you know upon the stabilization it can be folded into a different conformation and this is especially true when you look at sort of proteins that in that include more than one structural unions so those structural unions we call them protein domains essentially protein domain is a single unit that typically is evolutionary preserved that typically carries out the single function and typically has a very distinct fault structure 3d structure organization but turns out that if you look at human an average protein in a human cell would have to a bit of two or three such subunit and how they are trying to fold into the sort of you know next level fold right so within subunit is folding and then and then they fold into the larger 3d structure right and and all that there's some wonder saying the basic mechanisms but not to put together to be able to fold it we're still I mean we're still struggling I mean we're we're getting pretty good about folding relatively small proteins up to hundred residues which I mean but we're still far away from folding you know larger proteins and some of them are notoriously difficult for example transmembrane proteins proteins that that sit in the in the membranes of the cell they're incredibly important but they are incredibly difficult to solve and so basically there's a lot of degrees of freedom how it folds and so it's a combinatorial problem or just explodes there's so many dimensions Hey well it is a combinatorial problem but it doesn't mean that we cannot approach it from the non canal not from the boot for a force approach and so the machine learning approaches you know have been emerged that try to tackle it so folding at home I don't know how familiar with it but is that used machine learning or is it more brute force no so folding at home it was originally and I remember I was a it was a long time ago I was a postdoc and we we learned about this you know this game because it was originally designed as the game and we you know I took a look at it and it's interesting because it's it's really you know it's very transparent very intuitive so and from what I heard a via to introduce it to my son but you know kids are actually getting very good at folding the proteins and it was you know it came to me as they as the not as a surprise but actually as the sort of manifest of you know our capacity to do this kind of to solve these kind of problems when a paper was published published in one of these top journals with the coasters been the actual players of this game so and what happened is was that they managed to get better structures than the scientists themselves so so that you know that was very I mean it was kind of profound you know revelation that problems that are so challenging for a computational science maybe not that challenging for a human brain well that's a really good that's a hopeful message always when there's a the proof of existence the existence proof that it's possible that's really interesting but the it seems what are the best ways to do protein folding now so if you look at what deep mind does with alpha fall alpha fold yes so they kind of is that's a learning approach what's your sense I mean your backgrounds in machine learning but is this a learnable problem is this still a brute-force away in the garry kasparov deep blue days are we in the alphago playing the game of go days of folding well I think we are we are advancing towards this direction I mean if you look so there is a sort of olympic game for protein folders called CASP and it's essentially it's you know it's a competition where different teams are given exactly the same protein sequences and they try to predict their structures right and of course there's different sort of subtasks but in the recent competition half a fault was among the top performing teams if not the top performing team so there is definitely a benefit from the data that had been generated you know in the past several decades the structural data and certainly you know we are now at the capacity to summarize this data to generalize this data and to use those principles you know in order to predict protein structures as one of the really cool things here is there's maybe you can comment on it there seems to be these open datasets of protein how did that with the protein databank the a protein databank I mean as create is this a recent thing for just the corona virus or it's it's been for many many years I believe the first protein databank was designed on flash cards so on the so yes it's so this I mean this is a great example of the community efforts of everyone contributing cause every time you solve a protein or a protein complex this is where you submit it and you know the scientists get access to it scientists get to test it and we went from occasions use this information to you know to make predictions so there's no there's no culture like hoarding discoveries here so that's I mean you've you've you've released a few or a bunch of proteins they were matching its whatever we'll talk about details a little bit but it's kind of amazing that that's the the it's kind of amazing how open the culture here is it is and I think this pandemic actually demonstrated the ability of scientific community to you know to solve this challenge collaboratively and this is I think it if anything it actually moved us to a brand new level of collaborations of the efficiency in which people establish new collaborations in in which people offer their help to each other scientists offer their help to each other and publish results to it's very interesting we're now trying to figure out as a few journals that are trying to sort of do the very accelerated review cycle but so many preprints so just hosting a paper going out I think it's fundamentally changing the the way we think about papers yes I mean the way we think about knowledge now let's say no yes because yes I completely agree I think now it's the knowledge is becoming sort of the the core value not the paper or the journal where this knowledge is published and I think this is again this is we are living in the in the times where it becomes really crystallized that the idea that the most important value is in the knowledge so maybe you can comment like what do you think the future of that knowledge sharing looks like so you have this paper that will I hope you get a chance to talk about a little bit but it has like a really nice abstract and the introduction and related like it has all the usual I mean probably took a long time to put together so but is that going to remain like you could have communicated a lot of fundamental ideas here in much shorter amount that's less traditionally acceptable by the journal context so so well you know so the first version that we posted not even on a bi archive because by archive back then it was essentially you know overwhelmed with the number of submissions so so our submission I think it took five or six days to just for it to be screened and and and put online so we you know essentially we put the first pre pre n't on our website and you know it was started getting accessed right away so and and you know so this original preprint was in a much rougher shape than this paper and but we tried I mean we honestly try to be as compact as possible with you know introducing the the information that is necessary that to explain our you know our results so maybe you can dive right in if it's okay sure so it's a paper called structured of Tsarskoe how do you even pronounce our scurvy - Co V - yeah by The Cove it is such a terrible name but it stuck and yes Tsarskoe V - indicates evolutionary conserved functional regions of viral proteins so this is looking at all kinds of proteins that are part of the this novel coronavirus and how they match up against the previous other kinds of corona viruses and there's a lot of beautiful figures I was wondering if you could I mean there's so many questions I could ask her but maybe a tough how do you get started at doing this paper so how do you start to figure out the 3d structure of a novel virus yes so there is actually a little story behind it and so the story actually dated back in September of 2019 and you probably remember that back then we had another dangerous virus Triple E virus its eastern equine encephalitis virus and can you maybe linger in it I have to admit I was sadly completely unaware so so that was actually a virus outbreak that happened in New England only the the danger in this virus was that it actually it targeted your brain so so the word deaths from this virus it was it was transferred you know transfer the main vector was mosquitoes and obviously full-time is you know the time where you have a lot of them in New England and you know on one hand people realize this is this is this actually very dangerous thing so it had an impact on the local economy the schools were closed past six o'clock no activities outside for the kids because the kids were suffering quite tremendously from you know what infected from this virus and how do I not know about this was impacted it was in the news I mean it was not impacted to to high degree in in Boston necessarily but in the Metro West area and actually spread around I think all the way to New Hampshire Connecticut and you mentioned affecting the brain that's one other comment we should make so you mentioned a AC two for the corona virus so these viruses kind of attach to something in the body so it essentially attaches to the to these proteins in those cells in the body where those proteins are expressed where they actually have them in in abundance so sometimes that could be in the lungs that could be a brain that could be so I think what they right now from what I read they have the epithelial cells inside in so did the cells essentially inside the you know the it's the cells that are covering the surface you know so inside the nasal surfaces the this road the lung cells and I believe liver as a couple of other organs where they are actually expressing in abundance that's for the AC tuition for 318 two percenters okay so back back to the story yes in the fall so now the these you know the impact of this virus is significant however it's a pre local problem to the point that you know this something that we would call a neglected disease because it's not big enough to make you know the the drug design companies to design a new antiviral or in York seen it's not big enough to generate a lot of grants from the nation of finding agencies so so does it mean we cannot do anything about it and so what I did is I taught a by informatics class and is in Worcester Polytechnic Institute and we are very much problem learning institution so I thought that that would be a perfect you know perfect project in case study so so I asked it you know so so I we essentially designed a study where we tried to use by informatics to to understand as much as possible about this virus and a very substantial portion of the study was to understand the structures of the proteins to understand how they interact with with each other and with the with the host proteins try to understand the evolution of this virus it's obviously you know a very important question how where it will evolve further how you know how it happened here you know so so we did all this you know projects and now I'm trying to put them into a paper where all these undergraduate students will be coasters but essentially the projects were finished right about mid-december and a couple of weeks later I heard about this mysterious new virus that was discovered in you know was reported in in Wuhan province and immediately I thought that well we just did that can't we do the same thing with this virus and so we started waiting for the genome to be released because that's essentially the first piece of information that is critical once you have the genome sequence you can doing a lot using my informatics when you see genome sequence that's referring to the sequence of letters that make up the RNA so the sequence that make up the entire information encoded in the protein right so so that includes all 29 genes what are genes what's the encoding of information sosigenes is essentially is a basic functional unit that we can consider so so each gene in the virus would correspond to a protein that so gene by itself doesn't do it function it needs to be converted or translated into the protein that will become the actual functional unit like you said the printer so so we need the printer for that we need to print it okay so the the first step is to figure out that the genome the sequence of things that to be then used for printing the protein so okay so then then the next step so once we have this and so we use the existing information about Sarkis the Czar's genomics has been done in abundance so we have different strains of SARS and actually other related coronaviruses MERS the bat coronavirus and we started by identifying the potential genes because right now it's just the sequence right it's a sequence that is roughly it's less than 30,000 nucleotide long and this the raw sequence it's a rose ignore the information really and we now need to define the boundaries of the genes that would then be used to identify the proteins and protein structures how hard is that problem it's not I mean it's pretty straightforward so you know so because we use the existing information about SARS proteins and SARS genes so once again we kind of we are relying on the yes so and then once we get there this is where sort of the first more traditional bind phonetic steps step begins we are trying to use these protein sequences and get the 3d information about those proteins so this is where we are relying heavily on the structure information specifically from the protein data bank that we are talking about and here you're looking for similar proteins yes so so the the concept that we are operating when we do this kind of modeling it's called homology or template based modeling so essentially using the concept that if you have two sequences that are similar in terms of the letters the structures of these sequences are expected to be similar as well and this is at the micro at a very local scale and at the scale of the whole protein at the whole protein I saw actually so you know so of course the devil is any details and this is why we need actually pre sophisticated modeling tools to do so once we get these structures of the individual proteins we try to see whether or not this proteins act alone or they have to be forming protein complexes in order to perform this function and again so this is sort of the next level of the modeling because now you need to understand how proteins interact and it could be the case that the protein interacts with itself and makes sort of a multi marek complex the same protein just repeated multiple times and we have quite quite a few such proteins in Tsarskoe v2 specifically spike protein needs three copies to function and load protein needs five copies to function and there are some other multimeric complexes that we mean by interacted with itself and you see multiple copy so how do you how do you make a good guess whether something's going to interact well again so there are two approaches right so one is look at the previously solved complexes now we're looking not at the individual structures but the structures of the whole complex complex is upon multiple proteins yes so it's a bunch of proteins essentially glued together and and when you say glued that's the interaction that's the interaction so so the different forces different sort of physical forces behind this as I certainly keep asking dumb questions but is it is the glue is that the interaction fundamentally structural or is it functional like in the way you're thinking about it that's actually a very good way to ask this question because turns out that the interaction is structural but in the way it forms this truck it actually also carries out the function so interaction is often needed to carry out very specific function or protein but in terms of an earth-sized figuring out you're really starting at the structure before you figure out the function so there's a beautiful figure two in the paper of all the different proteins that make up the able to figure out the makeup the the new the novel current virus what what are we looking at right so these are like that's this through the the step to the mentioned when you try to guess at the possible proteins that's what you're going to get is these blue blue cyan blobs yes so those are the individual proteins for which we have at least some information from the previous studies right so there is advantage and disadvantage of using previous studies the biggest well the disadvantage is that you know we may not necessarily have the coverage of all 29 proteins however the biggest advantage is that the accuracy in which we can model these proteins is very high much higher compared to a Benicia methods that do not use any template information so but nevertheless this figure also has incision beautiful and I love these pictures so much you've as it has like the pink parts yes there are the parts that are different so you're highlighting so the difference you find is on the 2d sequence and then you try to infer what I would look like on the 3d yeah so the difference actually is on 1d sequence one d1 design idea so and and so this is one of these first questions that we try to answer is that well if you take this new virus and you take the closest relatives which are SARS and a couple of bad coronavirus strains they are already the closest relatives that we are aware of now what are the difference between this virus and its close relatives right and what if you look DIPA Klee when you take a sequence those differences could be quite far away from each other so what make what 3d structure makes those difference to do they very often they tend to cluster together interesting and over sudden the differences that may look completely unrelated actually relate to each other and sometimes they are there because they correspond they attack the functional side right so they are there because this is the functional side that is highly mutated so that's a computational approach to figuring something out when when it comes together like that that's kind of a nice clean indication that there's something this could be actually indicative of what's what's happening yes I mean so we need this information and you know 3d the 3d structure gives us just a very intuitive way to look at this information and then start to ask you know start asking questions such as so this place of this protein that is highly mutated does it does it is it the functional part of the protein so does this part of the protein interact with some other protein so maybe with some other ligands small small molecules right so we would try now to functionally inform this 3d structure so so you have a bunch of these mutated parts is like I don't know how like how many are there in the new novel coronavirus being compared it's ours oh we're talking about hundreds of thousands like these these pink region all know did much less than that and it's very interesting that if you look at that you know so the first thing that you you start seeing right you know you look at patterns right and the first pattern that becomes obvious is that some of the proteins in the new coronavirus are pretty much intact right so they're pretty much exactly the same as SARS as the bat coronavirus where some others are heavily mutated so so it looks like that the you know the evolution is not is not a curing you know uniformly across the entire you know viral genome but actually target very specific proteins what do you do with that like from the Sherlock Holmes perspective well you know so one of the of the most interesting findings we had was the fact that the viral so the the binding sites on the viral surfaces that get targeted by the known small molecules the world pretty much not affected at all and so that means that the same small drugs or small small drug like compounds can be efficient for the new current a virus this all actually maps to the drug compounds - like so so you're actually mapping out what old stuff is gonna work on this thing and then possibilities for new stuff to work by mapping out the things I've mutated yes so so we essentially know which parts is in behave differently and which parts are likely to behave similar and again you know of course all our predictions need to be validated by experiments but hopefully that sort of helps us to delineate the regions of this virus that you know can be promising in terms of the drug discovery you kind of you kind of mentioned this already but maybe you can elabora
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