Pretty bacteria: Do not be fooled by the pastel colors- these things will kill you.
Courtesy esteraseI bet regular bacteria have posters of their favorite superbug hung on their bedroom walls. I mean superbugs are just so much cooler than regular bacteria; they’re kind of the bad boys of the bacteria world. Regular bacteria do what they are told: they keel over when exposed to disinfectants and antibiotics. But not those rebellious superbugs. Superbugs have some kind of genetic mutation that allows them to survive in hostile, antimicrobial environments. Basic principles of natural selection come into play: the mutant bacterium survives in the presence of the antibiotic/disinfectant and then goes on to produce other bacteria with the same mutation, ultimately creating a new resistant colony. In this scenario, exposure to the antimicrobial agent (the antibiotic or disinfectant) is imperative. However, scientists now think that another scenario exists; one in which exposure is not required. In a recent study, these scientists found that the use of disinfectants in hospitals can lead to bacterial resistance to antibiotics, even if the bacteria haven’t been exposed to the antibiotics.
Researchers from the National University of Ireland added increasing amounts of disinfectant to petri dishes full of Pseudomonas aeruginosa (a bug that causes pneumonia in hospital patients, among other things) and the bug became immune not only to the disinfectant, but also to ciprofloxacin- the antibiotic used to treat the bug. Superbugs are essentially using their exposure to disinfectants as “teachable moments” for resisting antibiotics.
This is significant because now it seems that bacteria have one less hurdle to overcome in their mission to cause serious harm to patients (that’s not really their “mission,” I say that for dramatic effect). If superbugs can resist the disinfectant slathered on the countertops and doorknobs of hospitals, it’s possible that they could go on to infect patients who “for some reason” won’t respond to the antibiotics. Man, regular bacteria must be so jealous.
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Richard Lenski (top) and Jeffrey Barrick view bacteria cultures in Lenski's lab.: They have watched the bacteria's DNA evolve over 40,000 generations.
Courtesy Michigan State University / photo by G.L. Kohuth
Sometimes you’ll hear people cast doubts on evolution because no one has ever seen it happen. As if that’s some sort of great insight. No one has eve “seen” atomic fusion, either, but the fact that the Sun was shining this morning is pretty strong evidence that, yep, it happens. No one has ever “seen” gravity. Seen gravity’s effects, sure. But seen gravity itself? Like Ms. Ono once asked, Who Has Seen The Wind?
Evolution used to be in the same boat. The effects of evolution are visible everywhere, in every cell of every living thing on the planet. But seeing the actual process of evolution? That was another matter.
Until now. Scientists at Michigan State University (go Spartans!) have been growing bacteria in bottles for the past 21 years. Every so often, they would freeze a sample for later study. Well, “later” is now. DNA sequencing and computer analysis have advanced to the state where they can readily map the genome of each sample. And guess what? The bugs evolved exactly as evolution says they should. Mutations in the genome pop up at random intervals. Mutations that help the bug survive—like make more efficient use of food, or fend off disease—get passed on to future generations, and eventually spread through the entire colony.
Twenty-one years may not seem like enough time for a species to change. But, as Mia Sorvino said in the truly awful 1997 movie Mimic, think generations, not time. In the two decades of study, the little bacteria went through 40 thousand generations—the equivalent of roughly 800,000 years in human terms. Plenty of opportunity for evolution to do it’s thang.
And the experiment continues. Understanding mutations in bacteria might help us understand the mutations that lead to some forms of cancer. In recent generations, the rate of mutation has increased; the scientists would like to know why.
Richard Lenski, the scientist heading up the research, has put together a video explaining his work.
These guys have been eating bacteria all day: That's all it takes!
Courtesy Dave AustriaHey y’all! Get a earful of this: Russian scientists claim to have found bacteria living in the superfrost that may be able to significantly extend our lifespans!
Whoa!
Oh, also, “superfrost” isn’t the word the original article used. In fact, “superfrost” isn’t a real word in the first place. The perpetually frozen sandy soil the bacteria were found in is actually called “permafrost.” I just invented the word “superfrost” because it was kind of cool in this post’s title. I also used the fake word to honor the original article, which contains an amount of information somewhere between zero and almost zero.
Maybe I shouldn’t have gotten my hopes up over a quasi-science article coming from a the Daily Mail, considering that the other stories on the page feature shots of the octuplet mother’s explosive looking belly, and Chris Brown leering over Rhianna’s shoulder… but it seems so cool! Seriously, this is sci-fi stuff!
What I can tell is this: Russian scientists were digging in an area of Siberia known for its abundance of wooly mammoth remains. Among the biological materials they recovered was a species of bacteria that appears to live in the permafrost. Finding it was an accident.
After doing a partial DNA analysis, the scientists determined that they were working with a unique type of bacteria. I don’t know if this means it’s a new species, genus, family, order, class, phylum, or kingdom… whatever. Probably not important, right, Daily Mail?
What’s interesting about the bacterium is that it appears to be very, very old. Three to five million years old, according to the article.
Say what, Daily Mail? Say what?!
I mean… What? Check out the wikipedia page on long-living organisms. With the exception of this weird jelly fish that could potentially live forever (we won’t get into it), 3-5 million years puts everything else on the list to shame. By far.
I’m guessing that the age was estimated based on the age of the associated mammoth remains in the area (they’re about 4.8 million years old), but how they know that the bacteria were alive at the same time as the mammoths isn’t explained.
Some scientists have made claims that certain bacteria might be able to remain in stasis for millions of years before being revived. But those claims are disputed, and, anyway, we’re talking about bacteria trapped in amber or salt deposits, not permafrost (which, despite the “perma,” has probably been considerably more dynamic over the last 5 million years than most amber).
If the bacteria were in stasis, which wasn’t suggested in the helpful article, that wouldn’t explain what the Russian scientists did with the bacteria next: they put it in some mice.
We aren’t talking gene therapy here, either. All the article says is that the mice were “vaccinated with the bacterium extract.”
That makes sense, right? I mean, I know turtles and parrots live a really long time, so if I’m always eating turtle soup and parrot cake, so I’m pretty much guaranteed to live a long time, right? And if I supplement that diet by shooting up some alligator (into my veins with a needle, say), I’ll be alive forever!
I don’t know. Somebody help me out here. Why would vaccinating yourself with a bacterium imbue you with properties of that bacterium? Wouldn’t it just help your immune system figure out how to kill that organism? I was vaccinated with weakened mumps virus, but, as far as I know, I don’t have the ability to make anyone’s face inflate on cue, nor did the process transform me into a protein shell full of bits of DNA.
Nonetheless, after their inoculation with the bacteria, the mice demonstrated “growth of physical, mental, and sexual activity” into their old age. Female mice were even able to give birth at an age equivalent to a human 70-year-old.
That’s freaking amazing, isn’t it? So, hmm… here at the Daily Mail, we seem to have an exclusive story on this awesome biological breakthrough. What should we title this story? What… should… we… call… it? I know! “'Pre-historic Viagra' found in Siberian mammoth DNA could boost your sex life and let you live longer”
Duh. I mean, it says in the article that the bacteria and the mammoths, though they were found in the same area, are not believed to be linked to each other, but nothing else makes sense, so why should the headline? Mammoth DNA! Pre-historic Viagra! Print it!
How frustrating. This seems awesome, but until I can get some better, and possibly less fake, information, I have to file it under “Thhhbbtttbbbtbb.” Fudge.
The flu and cold season is upon us, and with it the regular reminders to wash your hands. Check out this story – that tells you how many specific types of bacteria the average hand carries around at any particular time. And gals, you have even more reason to wash your hands than guys.
Studies have shown that, contrary to popular belief, mayonnaise actually inhibits the growth of bacteria and thus reduces the risk of food poisoning.
As the Mississippi flood waters recede, a new threat is rising. Public health officials in Iowa are warning people about the health risks associated with cleaning up their water-damaged homes, farms and buildings. Bacteria thrives in the water, and could lead to a number of diseases, and can contaminate well water. Water-logged buildings are a haven for mold, which can cause serious problems for allergy and asthma sufferers.
Researchers at Penn State have found a new species of bacteria in Greenland. Big whip – as long as it stays away from me, who cares? Well, this organism is ultra-small (I know what you’re thinking – aren’t bacteria pretty, um, small to begin with? Yeah, but these are super-duper small). It has also survived for 120 thousand years trapped without oxygen under two miles of ice. It may help scientists look for life on cold planets and moons elsewhere in our Solar System. (Which I think is a proper noun and therefore should be capitalized, though I may be mistaken.)
Scientists witness evolution in lab
in Cells, Heredity, Biological Populations Change Over Time, and Flow of Matter and Energy
For decades, scientists have been growing microbes in their labs and watching them evolve new traits. Most of the changes tend to be simple things, like an increase in size or growth rate.
But Dr. Richard Lenski of Michigan State University (just 2 miles from my house!) recently witnessed a major evolutionary leap--as it was happening. Twenty years ago, he took a colony of E. coli, a common bacteria, and split it into 12 identical populations. He’s been watching ever since to see if the strains evolve in different directions.
A few years ago, one of them did. One of his study strains suddenly evolved the ability to eat citrate, a molecule found in citrus fruits. No other E. coli in the world can do this, not even the other strains in Dr. Lenski’s lab. Even given several extra years and thousands of extra generations, the other strains are still citrate-averse. What’s more, the bacteria evolved this mutation entirely on their own, without any prodding or genetic manipulation from the researchers.
Lenski had saved frozen reference samples of all of his strains at regular intervals. Going back and growing new cultures from these samples, he again finds that only those from one strain ever evolve the citrate-eating habit – and only those sample less than about 10 years old. Lenski figures that some mutation happened around that time in one strain – and one strain only – that would later lead to citrate eating. He and his lab are now working on figuring out exactly what that mutation is.
It's an important job I've got for you...: That's right: pump my gas. I'm not getting out of the car.
Courtesy thefiveten77Using microorganisms to do our dirty work is all the rage these days. And, you know, they deserve it—they’ve spent so much time making us sick that they’re due for a little bit of productive action (and don’t bring up gut microbes, water treatment, or natural decomposition. I’m just not interested in anything that contradicts me).
It’s encouraging, then, to see that scientists in California have genetically engineered microorganisms (like yeast and strains of e. coli that eat organic garbage and poop crude oil. Is “poop” the right verb? It is? It’s exactly the right verb? Oh, good.
Currently the process requires a lot of equipment for a pretty small output. A room-sized computer and fermenting machine produces about a barrel of oil a week—America consumes about 143 million barrels of oil each week. And, at the moment, the process isn’t super cheap.
However, the scientists involved are hopeful that the necessary equipment can be shrunk, and the product can be produced more efficiently. With a commercial-scale facility (planned construction in 2011), using Brazilian sugarcane as feedstock (not the best crop, but that’s another post), oil could be produced at a cost of about $50 a barrel. Not bad, compared to the current price of oil hovering around $140 a barrel.
The process should be carbon neutral or negative too. That is to say, the CO2 produced by burning the fuel produced should be less than that pulled from the air by the feedstock materials.
It’s all very interesting, but I’m afraid that this sort of technology is forcing biotechnology away from its true purpose—microorganisms working for us in the very literal sense. The day e. coli wanders out into my yard and mows my lawn is the day I’ll get excited. Otherwise, what’s the point?
It is important to remember that not all microbes make you sick. In fact many are even helpful. Click here for a New York times article that summarizes recent findings or go to the original scientific article in
Genome Research about human skin microbes. Finally you can learn more about gut microbe research at Washington University here.
Why do microbes always get such a bad reputation?
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