July 4, 2013

Part II: Cells recycle old proteins; Redefining the unit of time; Superconductors are cool

2004 Nobel Laureate in chemistry Avram Hershko presented the history of his research resulting in…
“…the discovery of ubiquitin-mediated protein degradation.” - Nobel Foundation 2004
His work, along with fellow laureates Aaron Ciechanover and Irwin Rose, answered the following question. What happens to proteins as we age: do we keep the same proteins we’re born with or does biology break them down and recycle them throughout the course of our life?

Maybe to some this seems like a trivial question, of course cells are constantly breaking proteins down into their constituent components (amino acids) and building them back up. But before Hershko’s work, the question was non-trivial. To answer it, Hershko, Ciechanover, and Rose had to find the mechanism and show how it worked.

A big clue came from Schimke and Doyle in 1970 (Control of enzyme levels in animal tissue; Schimke, R.T. and Doyle, E.; Annu. Rev. Biochem;, 1970) where the rates of protein degradation were delineated. That is, proteins are not only broken down by cells, but the rate at which some proteins are recycled is different than for others.

The big discovery came when Hershko, Ciechanover, and Rose finally pinpointed the tag that cells use to mark proteins for degradation. This tag is actually a protein itself, ubiquitin. The authors discovered more than the tag, though. They discovered the whole pathway that can be taken by a protein during degradation. This discovery has immense implications for medicine and drug companies are really taking notice.

2005 Nobel Laureate in physics Theodor W. Hänsch presented a fun and informative lecture entitled, “What can we do with laser frequency combs?” based on his research…
“…contributions to the development of laser-based precision spectroscopy, including the optical frequency comb technique.” – Nobel Foundation 2005

Admittedly, I didn’t know much about laser frequency combs before Hänsch’s lecture and I was expecting to be blown to bits by a barrage of equations and jargon. But Hänsch totally nailed the lecture. I don’t recall seeing any equations, just really informative animations that conveyed a simple concept so you could understand something a bit more complex. Two slides stood out to me and luckily I was able to video them on my WinPhone.

So what are laser frequency combs good for? They deliver the awesome precision you need to understand why a clock on a satellite orbiting the earth is ticking a little bit slower than an identical one on earth. Why does time matter? When you’re a satellite moving at tens of thousands of miles per hour hundreds of miles above the earth, you experience weird phenomena called relativistic effects, and so the satellite needs to account for that. Without clever math and clever lasers those satellites that our GPSs talk to would be useless – miles and miles off. Of course it is way more complicated than just “clever math and clever lasers” and actually getting it all to work is so hard that you get a Nobel Prize for doing it. As Hänsch put it, you need a “passion for precision.” In fact Hänsch is so passionate about precision he proposed that the definition of “the unit of time” may soon be put to question!


1987 Nobel Laureate in Physics K. Alex Müller was the next presenter of the morning plenary lectures. His contributions to science are numerous but are popularly acknowledged to be for his… 
“…important breakthrough in the discovery of superconductivity in ceramic materials.” - Nobel Foundation 1987

You may have heard of superconductors and imagined a superhero using them to win the day. Superconducting is a quantum effect, meaning weird things happen for weird combinations of metals and oxygen (metal oxides).

Why should you care about superconductors? Well, scientific curiosity of nature and how it works, atom-by-atom, electron-by-electron (physicists takeover from chemists when you get smaller than electrons), can lead to unpredictably awesome advances in technology and thus society. If we can figure out how to make superconductors work efficiently at standard temperatures and pressures using relatively cheap materials, everything electrified will become much more efficient. Since they’re so expensive at the moment, you will probably only see a superconductor at a hospital or a big laboratory. But ten, twenty, thirty years from now, you may look up and see superconductors transporting electricity from a solar energy farm to your home, or in your cell phone, or in the sky driving an as yet not invented machine.

Three more Nobel Laureate Plenary Lectures are to come and sure to be awesome.

…kevin eduard hauser