Researchers at Harvard have come up with a novel way of studying how bacteria evolve to become drug resistant. They set up a large petri dish about the same shape as a football field with no antibiotics in the end zones and increasingly higher doses of antibiotics toward the center. They placed some bacteria in both end zones and filmed the results as the bacteria worked its way toward the center of the field, evolving drug resistance as it went. Ed Yong explains:
What you’re seeing in the movie is a vivid depiction of a very real problem. Disease-causing bacteria and other microbes are increasingly evolving to resist our drugs; by 2050, these impervious infections could potentially kill ten million people a year. The problem of drug-resistant infections is terrifying but also abstract; by their nature, microbes are invisible to the naked eye, and the process by which they defy our drugs is even harder to visualise.
But now you can: just watch that video again. You’re seeing evolution in action. You’re watching living things facing down new challenges, dying, competing, thriving, invading, and adapting — all in a two-minute movie.
Watch the video…it’s wild. What’s most interesting — or scary as hell — is that once the drug resistance gets going, it builds up a pretty good momentum. There’s a pause at the first boundary as the evolutionary process blindly hammers away at the problem, but after the bacteria “learn” drug resistance, the further barriers are breached much more quickly, even before the previous zones are fully populated.
Antonie van Leeuwenhoek ran a draper’s shop and was a local politician in Delft, Netherlands in the mid-17th century. During this time, he developed an interest in making lenses and hit upon a technique for making lenses with extremely high magnifications for the time, 270x and perhaps even 500x normal magnification. These lenses allowed him to discover that there were tiny organisms living in his mouth.
Ed Yong, Joss Fong, and Julia Belluz discuss van Leeuwenhoek’s achievement and microorganisms in general in the video above and in an interview.
It is undeniable that antibiotics have been a tremendous health good, maybe one of the greatest health goods of all time. They have brought so many infectious diseases to heel and saved so many lives.
But it’s also clear that they have negative effects on our microbiome. So they are indiscriminate weapons. They kill the microbes that we depend upon and that are good for us as well as the ones that are causing disease and causing us harm. They’re like nukes, rather than precision weapons.
So we’re in a difficult situation now, where on the one hand we’re running out of antibiotics, and the rise of antibiotic-resistant bacteria is a huge public health threat. But at the same time we’re aware of the need to preserve the microbiome.
Yong just came out with a book on microbes called I Contain Multitudes. (Perhaps Whitman was speaking literally?)
Crackerjack science writer Ed Yong is coming out with his very first book in a month’s time. It’s called I Contain Multitudes (good title!) and is about “astonishing partnerships between animals and microbes”.
Every animal, whether human, squid, or wasp, is home to millions of bacteria and other microbes. Ed Yong, whose humor is as evident as his erudition, prompts us to look at ourselves and our animal companions in a new light-less as individuals and more as the interconnected, interdependent multitudes we assuredly are.
The microbes in our bodies are part of our immune systems and protect us from disease. In the deep oceans, mysterious creatures without mouths or guts depend on microbes for all their energy. Bacteria provide squid with invisibility cloaks, help beetles to bring down forests, and allow worms to cause diseases that afflict millions of people.
I will read anything described as “like a David Attenborough series shot through a really good microscope”.
Update: Bill Gates liked I Contain Multitudes so much he sat down for a chat with Yong to discuss the particulars.
We are also utterly inseparable from them. Yong illustrates that we are at least as much microbe as human. We literally have more microbial cells living inside our bodies than human cells. And even the cells we label “human” are part microbe. With the exception of red blood cells and sperm, all our cells are powered by mitochondria, which are likely the descendants of ancient bacteria that became integrated into the type of cells that subsequently gave rise to all complex life.
Scientists have discovered the first promising new antibiotic in 25 years. And even better, says Ed Yong, is that the antibiotic in question is “resistant to resistance”.
A team of scientists led by Kim Lewis from Northeastern University have identified a new antibiotic called teixobactin, which kills some kinds of bacteria by preventing them from building their outer coats. They used it to successfully treat antibiotic-resistant infections in mice. And more importantly, when they tried to deliberately evolve strains of bacteria that resist the drug, they failed. Teixobactin appears resistant to resistance.
Bacteria will eventually develop ways of beating teixobactin — remember Orgel — but the team are optimistic that it will take decades rather than years for this to happen. That buys us time.
…and also that the process by which teixobactin was discovered is the real breakthrough:
Teixobactin isn’t even the most promising part of its own story. That honour falls on the iChip-the tool that the team used to discover the compound. Teixobactin is a fish; the iChip is the rod. Having the rod guarantees that we’ll get more fish-and we desperately need more.