Mmm... bacon....
I just spent an hour on the Nobel Prize web site reading and thinking about an old acceptance lecture, that of Dudley Herschbach. This is why I love Nobel week. It reminds me that people are smart. Lots of smart people are described as doing lots of smart things, and also it has the Otto Stern cigar story.
I'm going to do these out of order, because it will take less explaining this way. Trust me.
Nobel Prize in Chemistry
Ada Yonath, Venkatraman Ramakrishnan, and Thomas Steitz
(I put Ada Yonath's name first because she's a woman, and only four women have won a chemistry Nobel. My thesis advisor will, at the slightest provocation, tell you all about how Rosalind Franklin got screwed out of her share of the Prize with Watson and Crick, who discovered DNA. Franklin was dead at the time they got the prize, so she was ineligible. But I agree that she should get a lot more recognition than she does. Yonath was also the first person to get a crystal structure for a ribosome, so that's a good non-sexist reason to put her first.)
The chemistry prize frequently goes to advances in what should more properly be called biology. Or maybe that's just the physical chemist in me talking. Anyway, that's what happened this year, but since it involves my favourite molecule in the world, I am not too upset. Having never taken biology, I only learned about this in my fourth year of chemistry, in a "hah hah we'll review some stuff to start the semester" class. It was probably the greatest thing I learned that entire year, and that was the year I learned that you could wrap steaks in bacon.
So here's how life works. You have some DNA, which contains a bunch of chemicals in a certain order (they call this the genetic code). The DNA is divided up into parts, and when you stick some other chemicals on to hold them together, you get what are called chromosomes. The most famous are the X and Y chromosomes: women have two Xs, while men have one X and one Y. But DNA doesn't make you live, really. Chromosomes are what you get from your parents... not genes, as is commonly said. I mean, the genes are on the chromosomes, and sometimes spread across a few chromosomes, but it's really the chromosomes that are being passed on. (You got 23 from your mom, and 23 complementary ones from your dad, unless you have a genetic disease of some sort.)
Your body runs on proteins, which are these enormous (relatively speaking) molecules that actually do stuff, like make a nerve send a signal, tell your immune system to kill invaders, or make delicious bacon-wrapped steaks oh-so-nutritious. The trouble is in turning DNA into proteins. Imagine you have a long, thin strip of paper with holes punched in it. These holes, taken in groups, can be read as letters. That's DNA. Now, you're given a roomful of this paper and told to build the house that they describe. How are you going to do that?
The first step is to figure out what's written on the paper. You need a translator. Now, you could do this by hand, but you're smarter than that. You go buy yourself an old computer that can read ticker tapes, put a bit of the paper in, and tell it to read. In addition, you program the computer to figure out where every letter starts and ends, and to put it all into words, which it then makes sure are forward and not backward. Oh, and when the thing says, "get a hammer," the computer should scour your room for scrap metal, melt it down, carve a handle, and make you a hammer.
This is what a ribosome does! Holy cow! You have billions of these little computers inside your body, doing impossibly complex things!
So what the winners this year did was make crystals of these biological computers/factories, and use those to figure out what they look like. Why is this useful? Well, every species has roughly the same parts inside each cell, but there are a few small differences. In particular, bacteria have a slightly different ribosome than people do. (A few billion years of divergent evolution will do that.) So if you can make chemicals that destroy bacterial ribosomes, but not human ones, you can give it to a person and kill the bacteria in that person, but not the person. Hurrah! So knowing what the ribosome looks like means you can make computer models of it, and use those to develop antibiotics to cure sick people. Of course, there are many other uses, and we haven't discovered them all yet.
Science: making your life better since the day you were born.
Nobel Prize in Physiology or Medicine
Elizabeth Blackburn, Jack Szostak,and Carol Greider
Back in the 1970s, DNA had just been figured out, and molecular biology was getting exciting. Read the thing on chromosomes I wrote before. I told you I chose this order for a reason.
So how do you get a new set of chromosomes into a cell? How do you make copies of your chromosomes to pass onto your children? There is something called DNA replication, and it's done by a bunch of proteins, led by one called DNA polymerase. DNA comes in a pair of strands wound together, so to copy it, the DNA polymerase has to unwind the strand, copy it bit by bit, and wind it back up. It goes something like this:
1. find a "primer," which is a bit of DNA or RNA that splits the wound DNA strand
2. wait for the primer to attach, then attach to the primed DNA
3. loop:
3.1 look at the next bit of information
3.2 copy it and attach it to the last copied one (or the primer, at the start)
3.3 proofread and correct if necessary
4. when done, break off
Simple, right? Well, the hard part is the "when done" part. The end parts have a repeating sequence of 6 chunks of information, called a telomere. DNA polymerase can only work in one direction, and replication stops when a telomere sequence is reached (kind of), so the end telomeres get chopped off. If this happens enough times, then your chromosomes start to get too short to work. Not good!
How does the body overcome this? These researchers found a protein called telomerase. Blackburn found the repeating sequence that we now called a telomere. Szostak found out that chromosome fragments break down, and the two of them figured out that it was because of the telomeres. Then, Blackburn and Greider found out why: an enzyme called telomerase. Telomerase seeks out DNA and adds telomeres to the end.
This is important because telomeres are a big part of getting old. You age because your telomeres are getting shorter. They're also a big part of cancer: cancerous cells can divide quickly without dying because they create a lot of telomerase. And right now, people are curing cancer using this fact.
Nobel Prize in Physics
Charles Kao, Willard Boyle, George Smith
There are two different discoveries here, but the Nobel committee lumped them into a single prize. They're more engineering things than pure physics, but still useful.
Kao got half the prize for figuring out how to make fibre optics practical. Are you using the Internet? Then you are probably getting information that has been passed through fibre optics.
Fibre optics work by bending and reflecting light within a glass tube. Ever looked at your living room window at night and seen your reflection? Well, that reflection is how fibre optics work. Without going into it too much, Kao figured out that the reason early fibre optics weren't very good was that the glass wasn't pure enough. He did some calculations to show that it was possible, and then lobbied the right scientists to get it done.
Boyle and Smith worked at Bell Labs. I don't know how many Nobel Prizes have gone to people who've worked there, but I bet it's more than a couple. Great things come from Bell Labs. They invented the CCD, which is the electronic sensor used in your digital camera and cell phone, and also in most astronomical imaging equipment and modern medical imaging.
Think of a CCD like an ice cube tray, and the light coming in as rain drops. If light is brighter in one place, the hole in the tray corresponding to that will get full faster. Every once in a while, someone comes along and sucks up the water with a straw, and in that way figures out how the rain is distributed. That corresponds to light and dark areas in your photograph. Colour is just done by having three ice cube trays: one accepts only red water, one only green, and one only blue.
Giant ring around Saturn found
This is my favourite headline ever.
The Spitzer telescope, which observes in the infrared, has found a big ring that's farther out from Saturn than any other. They figure that it's due to material being kicked off one of the moons. The cool thing is that the material from this ring is coating one of the other moons, making the side of it going into the wind (so to speak) dark, like if you threw a snowball through a smoky room.
At the moment, Saturn is at equinox, so all the other rings are pretty much invisible from Earth. However, this new ring is tilted a bit, so it's clearly visible... well, if you can see infrared light.
An early ancestor of humans
I like this one because the discovery was made 17 years ago, but it was kept quiet until just now, so that good science could be done. It wasn't secret, but most of the people studying the fossil waited until the others were ready to publish, and they did it all together.
The main fossil described in these papers is named Ardipithecus, and is the oldest fossil from which we're descended since the split that lead to chimpanzees. It's 4.4 million years old: the famous Lucy (an Australopithecus) is a youthful 3.2 million, while the chimp split was about 6 million years ago.
The fossil is cool because it shows that there was a lot of evolution between the split and now. The most used example is that Ardipithecus has hands that aren't like any living great ape, but there are many more things like this.
The most important part is that we can't think of chimpanzees as being what our ancestors looked like. We never looked like chimps. Instead, we were something quite different, and became specialized to several different environments since. (A few million years from now, maybe our ancestors will have extra fingers so that they can type faster, and a few million after that, they will have none because they don't need to type any more.)
Artificial northern lights
This one's interesting because there's a conspiracy theory that the HAARP (High Frequency Active Auroral Research) program is using radio waves to control people's minds. Enough said on that. (The web site has a wicked cautionary statement, though.)
Basically, they have a radio station. A super-powered radio station. And way up north, there are lots of charged particles floating around in the atmosphere, because of the way the Earth's magnetic field directs particles from the Sun around. So they turn up the juice and start cranking their funky beats out to the radios of the reindeer and polar bears, and something cool happens.
When you bring a lot of ions close together, they collide, and electrons get bumped around, emitting light in the process. That's how the northern lights work: all the ions get close together near the pole, collide, and give off light. The radio waves have a magnetic field, and that directs the ions close enough to make this happen on command.
Recently, they've more than tripled their power output. What it means is that you can now see the light from the experiments. Before, they probably used radar or something to "see" it. (I admit, I skimmed that section.)
Their antenna shoots radio waves, which are, well, waves. So you get a pattern in the sky that looks like you just threw a rock into a pond. But what they found was that there were streaks coming out from the centre, like if your rock hit a bunch of beavers and they all started swimming away from the middle. They did some math and figured out that their radio waves were now powerful enough to cause some of the neutral (non-ionic) molecules to ionize... which meams those regions could light up, too.
So they're not just using the ions already in the atmosphere any more. They're making their own! I don't know if it's direct ionization (knocking electrons off with each radio wave hit), or if there is something more complicated going on, but I bet it's a bit of both. (If they need someone good with molecular dynamics for modelling work.... *waves hand wildly in the air*)
That's the end of our flagship issue! I hope you enjoyed it. Suggestions are much appreciated. I'm thinking of maybe breaking future issues into smaller segments, stealing pictures to go with articles, and a couple other things.
Until next time, stay sciency!
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