Rise of the Superbug AntibioticResistant Bacteria Karl Klose at TEDxSanAntonio
Antibiotics were the wonder drugsof the 20th century. Now, amazingly antibiotics are responsible for extending the average human lifeabout ten years. But we are currently in the middleof a global crisis where antibiotics are loosing their effectiveness against infectious diseases. The headlines, if you can see them,are very alarming. Bacteria are rapidly becoming resistant
to all of the antibiotics that we currently use. Now, in order to understandthe nature of this problem, you have to understand bacteria. We live in a world filled with bacteria. Bacteria are everywhere. Everything that you look at, everything you touch, everything you put in your mouth,
everything you sit on is covered with millions and millions of bacteria. They're so small that you can't see themwithout a microscope. But they're there.And they are literally everywhere. You can find them at the bottomof the deepest part of the ocean. You can find themat the top of the tallest mountain. You can even find themin the polar ice caps.
They can live in placeswhere there is no sunlight, no oxygen, no food. They can grow in radioactive waste, and in toxic chemicals, and in boiling hot springs. When bacteria find a placewhere they can survive, they'll multiply fast to very high numbers. Now, one of the placesthat bacteria like to call home
is the human body. A recent survey by microbiologists identified over ten thousand different microbes that live on, or in the human body. In fact, there are more bacterial cells in you than there are human cells. And there are more bacteria genes in you than human genes.
So you can argue that each one of you is actually more bacteriumthan you are human. (Laughter) So, now we have established that I am talking to a room full of bacteria (Laughter) I'm going to flatter the audiencehere a little bit and tell you that bacteriaare amazing organisms.
The Antibiotic Apocalypse Explained
What would you say if we told youthat humanity is currently making a collaborative effort toengineer the perfect superbugé A bug that could kill hundredsof millions of peopleé Well, it is happening right now. We are in the processof creating a superbacterium. Bacteria are among the oldestliving things on this planet. The smallest thing we still consider life,they are masters of survival and can be found everywhere.
Most bacteria are harmless to us. Your body hosts trillions of them,and they help you to survive. But others can invade your body,spread quickly, and kill you. Millions of people used to die as a resultof bacterial infections. Until we developeda superweaponâ€”antibiotics. Together with vaccinations, antibioticsrevolutionized medicine and saved millions of lives. Antibiotics kill the vast majority ofsusceptible bacteria fairly quickly,
leaving only a small group of survivors that our immune systemthen deals with easily. How do antibiotics do thisé Imagine a bacterium asa very complex machine with thousands of complex processesgoing on that keep it alive and active. Antibiotics disruptthis complex machinery, for example, byinterfering with its metabolism, slowing down their growth significantly,so they are less of a threat.
Other antibiotics attack DNAand prevent it from being replicated, which stops bacteria from multiplying,ultimately killing them. Or by simply ripping the outer layerof the bacteria to shreds, so that their insides spillout and they die quickly. All of this without bothering body cells. But now, evolution is makingthings more complicated. By pure random chance, a small minorityof the bacteria invading your body might have evolved a wayto protect themselves.
For example, by interceptingthe antibiotics and changing the moleculeso it becomes harmless. Or by investing energy in pumpsthat eject the antibiotics before they can do damage. A few immune bacteriaare not that big a deal, because the immune systemcan take care of them. But if they escape, theymight spread their immunity. How can bacteria spread immunityé
First of all, bacteriahave two kinds of DNA: the chromosome and smallfreefloating parts called plasmids. They can hug each otherand exchange those plasmids to exchange useful abilities. This way, immunity can bespread quickly through a population. Or, in a process called transformation,bacteria can harvest dead bacteria and collect DNA pieces. This even works betweendifferent bacteria species
What causes antibiotic resistance Kevin Wu
What if I told you there were trillionsof tiny bacteria all around youé It's true. Microorganisms called bacteriawere some of the first life forms to appear on Earth. Though they consist of only a single cell, their total biomass is greater thanthat of all plants and animals combined. And they live virtually everywhere: on the ground, in the water,
on your kitchen table, on your skin, even inside you. Don't reach for the panic button just yet. Although you have 10 timesmore bacterial cells inside you than your body has human cells, many of these bacteriaare harmless or even beneficial, helping digestion and immunity. But there are a few bad applesthat can cause harmful infections,
from minor inconveniencesto deadly epidemics. Fortunately, there are amazing medicinesdesigned to fight bacterial infections. Synthesized from chemicals oroccurring naturally in things like mold, these antibiotics killor neutralize bacteria by interrupting cell wall synthesis or interfering with vital processeslike protein synthesis, all while leaving human cells unharmed. The deployment of antibioticsover the course of the 20th century
has rendered many previouslydangerous diseases easily treatable. But today, more and moreof our antibiotics are becoming less effective. Did something go wrongto make them stop workingé The problem is not with the antibioticsbut the bacteria they were made to fight, and the reason lies in Darwin's theoryof natural selection. Just like any other organisms, individual bacteriacan undergo random mutations.
Many of these mutationsare harmful or useless, but every now and then,one comes along that gives its organism an edge in survival. And for a bacterium, a mutation making it resistantto a certain antibiotic gives quite the edge. As the nonresistant bacteriaare killed off, which happens especially quicklyin antibioticrich environments,
like s, there is more room and resourcesfor the resistant ones to thrive, passing along only the mutated genesthat help them do so. Reproductionisn't the only way to do this. Some can release their DNA upon deathto be picked up by other bacteria, while others use a methodcalled conjugation, connecting through pilito share their genes. Over time, the resistantgenes proliferate,