[HN Gopher] New superbug-killing antibiotic discovered using AI
       ___________________________________________________________________
        
       New superbug-killing antibiotic discovered using AI
        
       Author : tsenapathy
       Score  : 137 points
       Date   : 2023-05-25 15:07 UTC (7 hours ago)
        
 (HTM) web link (www.bbc.com)
 (TXT) w3m dump (www.bbc.com)
        
       | jbullock35 wrote:
       | In the title of this post, it would help to have a hyphen between
       | "Superbug" and "killing," as in the BBC article. When I first
       | read the title of this HN post--without the hyphen--I thought the
       | article was going to be about a dangerous new superbug that is
       | defeating antibiotics.
        
       | 71a54xd wrote:
       | Hopefully they can finally apply something to combat C. Difficile
        
         | Fomite wrote:
         | There's a lot of research into ways to treat C. difficile.
         | 
         | Some of it is genuinely antimicrobial stewardship - keeping
         | people off proton pump inhibitors and certain classes of
         | antibiotics.
         | 
         | Fecal transplant is also getting both more viable and better
         | understood (this is what I worked on for my dissertation).
         | 
         | There's also some investigation of alternative therapeutics for
         | C. diff that aren't just vancomycin.
        
       | hedora wrote:
       | I read this as "AI-equipped superbugs have figured out how to
       | kill antibiotics," which almost makes enough sense to be bad
       | headline.
        
       | stuff4ben wrote:
       | This is where we need to see more investment in AI. Not always
       | replacing humans, but rather augmenting and helping them. Sure
       | there are efficiency gains that are needed in a capitalist
       | society that AI can help with, but I'd rather see gains in other
       | areas.
        
         | ChatGTP wrote:
         | I feel the same, it would be a much nicer and less agitating
         | goal and much more inline with all the "promises" which have
         | been made for the last 10-20 years about why we should be
         | excited and invest in AI development.
         | 
         | The talking computers goals are "weird", the getting help with
         | solving problems part seems more sane.
        
         | carlmr wrote:
         | Honestly it's much more likely anyway, the AI hype will die
         | down a little again soon, leading to a more realistic view of
         | AI being a better personal assistant now.
        
       | manicennui wrote:
       | I really wish we would use more precise terminology when
       | discussing and reporting on these things. It sounds like they
       | used machine learning, and I wish we'd stop calling all machine
       | learning AI, but that ship has probably sailed.
        
         | drabbiticus wrote:
         | The ship has definitely sailed. See
         | https://ai.engineering.columbia.edu/ai-vs-machine-learning/
         | which states:
         | 
         | > Artificial intelligence (AI) and machine learning are often
         | used interchangeably, but machine learning is a subset of the
         | broader category of AI.
         | 
         | and
         | 
         | > Machine learning is a pathway to artificial intelligence.
         | This subcategory of AI uses algorithms to automatically learn
         | insights and recognize patterns from data, applying that
         | learning to make increasingly better decisions.
        
       | [deleted]
        
       | kylehotchkiss wrote:
       | Great, keep the recipe under wraps, never allow it to be
       | manufactured abroad, and only allow hospitals to distribute it.
       | Otherwise this is just going to become the frontline antibiotic
       | given whenever somebody gets so little as a cough in most of the
       | world :/. The problem with our existing antibiotics was how
       | generously they were given out to anybody with any symptom.
        
         | droopyEyelids wrote:
         | This point is moot because the antibiotics will be manufactured
         | overseas where all the waste & runoff is discarded by pumping
         | it into local rivers, causing ecosystem wide adaptation to the
         | material.
         | 
         | This is currently the situation in India, where the bulk of our
         | antibiotics are manufactured.
        
         | drabbiticus wrote:
         | Your comment is grounded in some truths and yet in this
         | specific instance is very off base.
         | 
         | From the article:
         | 
         | > Curiously, this experimental antibiotic had no effect on
         | other species of bacteria, and works only on A. baumannii.
         | 
         | This is an oversimplified claim made by the BBC article, but
         | broadly aligns with the research paper claim that the
         | identified drug is specifically not broad-spectrum and not
         | active against e.g. Pseudomonal and Staphylococcal species. The
         | identified drug candidate is unlikely to ever see broad use
         | because of the low activity against many clinically relevant
         | bacteria.
         | 
         | The most common use case for this candidate, should it see
         | approval through the FDA process for this indication, will be
         | for treatment of hospitalized patients who, while waiting for
         | culture results, have failed broad-spectrum regimes and whose
         | culture results demonstrate Acinetobacter infections.
        
         | protastus wrote:
         | Regulate the veterinary use too. Some antibiotics have seen
         | unrestricted large scale use with livestock.
        
           | Fomite wrote:
           | This helps, but doesn't solve the problem entirely. We have
           | some data showing cattle with antibiotic resistant E. coli to
           | antibiotics that are _not_ administered to livestock, because
           | they 're carried on the same plasmids as other resistance
           | genes that confer a fitness advantage in some other way (i.e.
           | another antibiotic, heavy metals, etc.)
           | 
           | That's not to say that regulating its use isn't a good idea,
           | just that it's _really complicated_.
        
         | analog31 wrote:
         | Not to mention mixing antibiotics with livestock feed to
         | promote growth.
        
       | TechRemarker wrote:
       | Since the the author presumably copied and pasted the original
       | title, assuming the remove of the "-" was intentional to make
       | more click baity since then reads as if someone is using AI to
       | create superbugs that can kill anti biotics rather than of course
       | what the actual article said which was an antibiotic that is
       | superbug-killing.
        
       | ARandomerDude wrote:
       | I spent a second trying to understand why anyone would do this
       | (gain of function research?), until I realized the title should
       | have retained the BBC's hyphen.
       | 
       | > Superbug killing antibiotics with the help of AI
       | 
       | means "A superbug is killing antibiotics, with the help of AI."
       | 
       | > Superbug-killing antibiotics with the help of AI
       | 
       | means "Antibiotics are killing a superbug, with the help of AI."
        
         | account-5 wrote:
         | Same here. Exact same though until I read the article and
         | realised it was the opposite of what I thought.
        
         | 0xcafecafe wrote:
         | I had a similar brush with ambiguity sometime back when there
         | was an article about a bill being tabled. The verb table has
         | two opposite meanings per merriam webster:
         | 
         | https://www.merriam-webster.com/dictionary/table#:~:text=tab...
         | 
         | a: to remove (something, such as a parliamentary motion) from
         | consideration indefinitely b British : to place on the agenda
        
         | ljlolel wrote:
         | [flagged]
        
           | hombre_fatal wrote:
           | [flagged]
        
       | yyyk wrote:
       | >They took thousands of drugs where the precise chemical
       | structure was known, and manually tested them on Acinetobacter
       | baumanni... This information was fed into the AI... The AI was
       | then unleashed on a list of 6,680 compounds... took the AI an
       | hour and a half to produce a shortlist... The researchers tested
       | 240 in the laboratory, and found nine potential antibiotics.
       | 
       | They started with manually testing thousands of drugs, in order
       | to narrow another similarly sized list by one order of magnitude,
       | which was then tested manually. Did they actually save time
       | compared to what it would have taken to test the 6,680 list
       | manually? I guess this needs to go up by one order of magnitude
       | to be really worthwhile?
        
         | adventured wrote:
         | It's worthwhile to begin trying to use AI for these purposes.
         | The only way we get from here to there, is by using this tech
         | in its early forms today, exploring with it, experimenting with
         | it. Let's see what it can do, learn, adjust, push it further.
         | 
         | The 10x better version of it from the future doesn't just
         | appear out of nowhere. We get there by step.
        
           | joejerryronnie wrote:
           | I'm worried about the 10,000,000x version which may emerge
           | organically at some point in time.
        
         | tehjoker wrote:
         | Maybe it was easier to culture the original bug?
        
         | Thorrez wrote:
         | Where does it say they manually tested thousands? It sounds to
         | me like they manually tested 240.
        
           | yyyk wrote:
           | The first sentence I quoted. They used thousands to train the
           | AI, and then ran the AI on a similar sized list. Perhaps with
           | reuse it will be worthwhile. Or the second list was harder to
           | synthesize?
        
             | Thorrez wrote:
             | Oop, I need to read better...
        
           | sp332 wrote:
           | If you scroll down past the second photo, right after the
           | heading "Artificial intelligence".
        
         | mcdonji wrote:
         | I think the effort in the testing of the thousands of drugs was
         | to help create the AI model. Then they used that model and it
         | seems to have identified a promising antibiotic. The next time
         | they go through the process they would not need to train the
         | model again right? So get another big list of chemicals and run
         | them through the model.
        
           | YeGoblynQueenne wrote:
           | Reading the study's abstract, there will not be a "next time"
           | because the dataset they created, and the model they trained,
           | was specific to Acinetobacter baumannii:
           | 
           |  _Here we screened ~7,500 molecules for those that inhibited
           | the growth of A. baumannii in vitro. We trained a neural
           | network with this growth inhibition dataset and performed in
           | silico predictions for structurally new molecules with
           | activity against A. baumannii. Through this approach, we
           | discovered abaucin, an antibacterial compound with narrow-
           | spectrum activity against A. baumannii._
           | 
           | https://www.nature.com/articles/s41589-023-01349-8
           | 
           | Not only were both the dataset they created, and the model
           | they trained on it, specific to one organism, the drug they
           | discovered also only works on that one organism ("narrow
           | spectrum activity against A. baumannii"). If they wanted to
           | discover drugs that work on other organisms, like
           | Staphylococcus aureus and Pseudomonas aeruginosa that the BBC
           | article mentions, they'd have to start all over again.
           | 
           | So, not an approach that looks very practical at this time.
           | Maybe in the future, when the sample efficiency and
           | generalisation ability of neural nets has significantly
           | improved it will be useful in practice.
           | 
           | Study:
           | 
           | https://www.nature.com/articles/s41589-023-01349-8
        
           | geph2021 wrote:
           | I think the effort in the testing of the thousands of drugs
           | was to help create the AI model.
           | 
           | This gets to the crux of my skepticism around the big claims
           | around the pace of AI advancement. At a fundamental level the
           | upper limit of AI advancement, in any area, is "the speed of
           | information". For some areas, like pharmaceutical/drug
           | development, the information comes from the real world,
           | human/biological processes (e.g. clinical drug trials), which
           | take time. At the extreme, the outcomes of interest could be
           | long-term (i.e. years or decades). AI surely advances
           | analytically capabilities, but ultimately models can only be
           | developed or refined with new data/information, which unfolds
           | at a rate that may be independent of computational speeds. AI
           | models that are highly predictive and valuable by definition
           | necessitates a feedback loop that is tied back to real-world
           | outcomes/timescales.
           | 
           | I'm no expert on AI, but I get this sense that the
           | exponential improvements that many believe will lead to the
           | singularity may in fact reach an inflection point where the
           | curve flattens out becomes linear or asymptotic, as the rate
           | of improvement is governed by the rate of new information in
           | the real world.
        
             | chrisco255 wrote:
             | Even for existing information, there remains an enormous
             | amount of contextual / cultural / insider knowledge about
             | the world that is not documented in any digestible way by
             | an AI.
        
               | pixl97 wrote:
               | For the moment. Things like gpt-4 are already multimodal,
               | but not widely deployed in that fashion. Your data may
               | just be a smart Webcam on wheels away from being
               | ingested.
        
             | agentofoblivion wrote:
             | You hit the nail on the head, and I train transformers for
             | a living. This pervasive axiom that intelligence can just
             | scale exponentially at a rapid pace is rarely questioned or
             | even stated as an assumption. It's far from clear that this
             | is possible, and what you've outlined is a plausible
             | alternative.
        
               | pixl97 wrote:
               | It depends on the scaling nature of the problem being
               | researched. If it's one like the '9 months to make a
               | baby' issue, then you can't really reduce the minimum
               | time. On the other hand if it's studying bacteria with a
               | fast breeding rate, then expanding to hundreds of
               | thousands of AI Petrie dishes is apt to rapidly
               | accelerate the study of the problem.
        
             | ajuc wrote:
             | It's possible that no new information is needed, just
             | better analysis.
        
         | drabbiticus wrote:
         | Science journalism frequently oversimplifies scientific
         | investigation. This comment will similarly make
         | simplifications, but hopefully overall will provide more
         | clarity.
         | 
         | > The AI was then unleashed on a list of 6,680 compounds whose
         | effectiveness was unknown. The results - published in Nature
         | Chemical Biology - showed it took the AI an hour and a half to
         | produce a shortlist.
         | 
         | "published in Nature Chemical Biology" is a link you have to
         | click to see the article in fulltext, which I would encourage
         | you to read if you really want to understand the study. I would
         | link it directly, but there is some site-referrer magic
         | happening that allows the BBC article link to cause Nature
         | publishing group to show the fulltext.
         | 
         | To better understand what was done:
         | 
         | Training set (manually tested): off-patent drugs (2,341
         | molecules) and synthetic chemicals (5,343 molecules). In
         | particular the synthetic chemicals are likely to have
         | unacceptable side effect profiles. Result of manual screen: 480
         | molecules capable of inhibiting Acinetobacter growth by 20%.
         | 480/(2341+5343) = 6-7%
         | 
         | Result of AI processing and additional filtering criteria:
         | model applied to "Drug Repurposing Hub" dataset consisting of
         | 6,680 molecules which they claim have demonstrably favorable
         | cytotoxicity profiles and drug-like properties and yielding 3
         | sets of 240 drugs each. The three sets:
         | 
         | 1. 240 drugs identified by the model as having >20% probability
         | of at least 20% growth inhibition of Acinetobacter and
         | structurally _dissimilar_ to those with antibiotic activity in
         | the training set. Manually testing for those capable of more
         | stringent criteria (80% inhibition of growth) yielded 9 drugs.
         | 
         | 2. 240 drugs with lowest prediction scores: Manual testing
         | yields no active drugs, providing some basic validation that
         | classifier is functional.
         | 
         | 3. 240 drugs with highest prediction scores (without additional
         | filtering criteria based on structural dissimilarity): Manual
         | testing yields 40 drugs capable of 80% inhibition. 40/240 =
         | 16-17%. Yield enrichment: 16%/6% = 260% or a 2.6x improvement
         | compared to naive screen of training set. To be fair, this
         | isn't a direct claim of the paper for good reason: the drugs in
         | their training set and "validation set/drug repurposing hub"
         | are fundamentally different and may have different baseline
         | antibiotic activity across the set.
         | 
         | The process of narrowing down these datasets using the model
         | could be accomplished in hours (their claim) instead of days
         | (my claim). Days is optimistic prediction, requiring high-
         | throughput systems and/or staffing in place to run these
         | screening assays mostly in parallel instead of serially. Also
         | prevents costs associated with further biochemical
         | investigation (cultures, chemical synthesis and assays are not
         | free).
         | 
         | Most direct value of this work is in accelerating drug
         | screening process, reducing cost and developing AI-tractable
         | representations of pharmaceutically-relevant chemical features.
         | Additionally, proof of concept for identifying drugs with
         | appropriate side effect profiles that happen to have antibiotic
         | activity but would not have been identified with
         | existing/common structural analysis approaches, since they are
         | structurally dissimilar to the testing dataset screen. In this
         | case they identified a "CCR2- selective chemokine receptor
         | antagonist" that had antibiotic properties; some googling
         | suggests that this drug class mostly has roles in
         | fibrosis/inflammation regulation and may have roles in
         | autoimmune disorders and those with significant fibrosis as
         | part of the pathology (e.g. cardiovascular disease, liver
         | disease, diabetes). You wouldn't expect most drugs in this
         | class to have any antibiotic properties and many companies
         | would not focus their first efforts on screening such drugs
         | with biochemical assays.
        
           | YeGoblynQueenne wrote:
           | Why can't you see the full text? Try this link:
           | 
           | https://www.nature.com/articles/s41589-023-01349-8
           | 
           | I copied it from the Nature article, where I got to from the
           | BBC link. The Nature page has the full text (I'm not logged
           | in). I'm on firefox, is it your browser?
           | 
           | Edit: Oh, wait, I am logged in to Nature. But only on
           | firefox. When I switch to chrome and try navigating to the
           | Nature article by clicking the BBC link, I get a paywall.
           | What exactly do you see on your side?
        
         | bb123 wrote:
         | They probably didn't save much time but you must think of the
         | positive things mentioning the AI buzz word will have done for
         | their funding.
        
           | 0gravitas wrote:
           | And, of course, further research is needed...
        
         | throwuwu wrote:
         | Now that they have a trained model they can continue to apply
         | it to new chemicals. It could even be used on chemicals that
         | have not been synthesized yet to check if they are useful and
         | worth the effort and money to synthesize.
        
         | kurthr wrote:
         | Hopefully, soon we can start treating all the cattle in the US
         | with low doses of this drug, and dumping failed manufacturing
         | batches in the Ganges river.
         | 
         | Think of the poor superbugs!
        
           | tohnjitor wrote:
           | Hopefully you are personally unable to implement such plans
           | because antibiotics are not without their side effects. It
           | took twelve years between Levaquin becoming FDA approved in
           | 1996 and the addition of a black box warning label in 2008
           | due to risk of Achilles tendon rupture.
           | 
           | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2483892/
        
             | andrewnicolalde wrote:
             | I suspect they were being sarcastic.
        
         | nestorD wrote:
         | My guess is that they tested thousands of _existing_ drugs
         | (cheap to produce and easily available) in order to build a
         | short list of _new_ compound (significantly more expensive to
         | produce).
        
       | bazmattaz wrote:
       | This is incredibly exciting stuff and all I keep thinking of is
       | why the hell aren't governments pouring money into research like
       | this?
       | 
       | ML models like this need training examples and The article talks
       | about manual testing thousands of compounds to gather enough
       | training data. This is where lots of money could have a huge
       | benefit. The more high quality data a model has the better it's
       | accuracy
        
         | droopyEyelids wrote:
         | The way governments pour money into this is by funding grants
         | at research universities.
         | 
         | This came out of McMaster, though, and I don't know if the
         | Canadian government does funding the same way as we do in the
         | USA.
         | 
         | Still it raises an ugly question, why can discoveries funded by
         | the citizens of a country be turned into the patented property
         | of private companies.
        
           | Fomite wrote:
           | Canadian and U.S. research funding work _very_ differently
        
         | Fomite wrote:
         | What makes you think they aren't?
         | 
         | I can name four or five labs _on my floor_ that are currently
         | working on various aspects of antimicrobial resistance, all of
         | which are government funded.
        
       | greenhearth wrote:
       | How long before AI recombines DNA for creature creation?
        
       | sklargh wrote:
       | This is a heartening affirmative use. The negative of this image,
       | creating biological warfare agents with extraordinary virulence
       | and/or infectiousness is terrifying. Not really sure who would or
       | how to begin reducing those risks.
        
         | m3kw9 wrote:
         | And equally use AI to neutralize these new diseases, if there
         | are scientists left
        
       | RobinL wrote:
       | If anyone's wondering in what way AI/ML was used, here's the
       | relevant part of the article:
       | 
       | >>> We first screened a diverse collection of 7,684 small
       | molecules at 50uM for those that inhibited the growth of A.
       | baumannii ATCC 17978 in Lysogeny Broth (LB) medium (Fig. 1b and
       | Extended Data Fig. 1a). This chemical collection consisted of
       | both off-patent drugs (2,341 mol-ecules) and synthetic chemicals
       | (5,343 molecules) curated from various high-throughput screening
       | sub-libraries at the Broad Institute. Using a conventional hit
       | cutoff of one standard deviation below the mean growth of the
       | entire dataset resulted in 480 molecules being defined as
       | 'active' and 7,204 being defined as 'inactive' (Supplementary
       | Data 1).Next, this dataset was used to train a binary classifier
       | to predict whether structurally new molecules may display
       | activity against A. baumannii. Briefly, we leveraged a directed
       | message-passing neural network architecture, which translates the
       | graph structure of a mol-ecule into a continuous vector18 (Fig.
       | 1a).This type of model operates by iteratively exchanging
       | informa-tion of local chemistry between adjacent atoms and bonds
       | in a series of 'message-passing' steps. Each iteration of message
       | passing propa-gates information about local chemistry across the
       | molecule, thereby allowing the model to build a more holistic
       | representation of the mol-ecule. After a defined number of
       | message-passing steps, the vector representations of various
       | local chemical regions of a molecule are summed into a single
       | continuous vector that captures the complexity of the entire
       | compound. This learned final vector is then supplemented with
       | fixed molecular features computed using RDKit19. A final vector
       | containing both learned and computed features is then used as an
       | input vector for a feed-forward neural network that predicts
       | antibacterial properties. The model was further optimized by
       | using an ensemble of ten classifiers, increasing its robustness.
       | Our final model achieved an area under the precision-recall curve
       | of 0.337+-0.088 and an area under the receiver-operating
       | characteristic curve of 0.792+-0.042, providing confidence in
       | leveraging the model for predictions in new chemical spaces.
        
         | tedunangst wrote:
         | > small molecules at 50uM
         | 
         | That's an unusual unit.
        
         | twic wrote:
         | My question is how this compares to other methods for drug
         | design. They are not the first people to use a computer to pick
         | molecules out of a library to test as antibiotics. Is their
         | method much better, a bit better, no better, etc? That doesn't
         | seem to be mentioned in the discussion.
        
       | arbuge wrote:
       | 1. That is of course awesome.
       | 
       | 2. I read about this and see Nvidia up in the news by another 20%
       | today and it makes me think. The old economy "value stocks" in
       | comparison, which are popularly considered to have no exposure to
       | AI, are being dumped by the wayside. But AI advances will benefit
       | those same old economy stocks in many cases. They still possess
       | the necessary distribution to bring them them to market
       | effectively. It's traditional drug companies in this particular
       | example that are best positioned to capitalize on this.
        
       ___________________________________________________________________
       (page generated 2023-05-25 23:01 UTC)