musseling flexible strength with metals

Mussels (and geckos) exploit all sorts of crazy chemistry that scientists are still trying to understand and learn from. Geckos’ feet are the ultimate post-it notes, sticking and unsticking to surfaces without any glue. Mussels coat their “feet” in a natural protein super-glue. Some scientists are even trying to combine the two features. I’ve written about this chemistry before, and I like to keep track of what’s going on with this sticky science.

Credit: American Chemical Society
Damaged mussel byssal thread, Credit: American Chemical Society

There’s been a lot of discussion about mussels, but scientists have uncovered how these creatures marry their super-strength with flexibility on the byssal threads that attach them to solid surfaces. Most human-made coatings have to sacrifice one feature to gain on the other. The proteins on the surface of the threads contain many copies of a sticky molecule, dopa (3,4-dihydroxyphenyl-L-alanine), but that’s not enough to keep the surface hard. The proteins need the power of iron and calcium ions to keep the surface from cracking. The metal ions glom onto (chelate) the many oxygen atoms in the dopa groups and make them twice as hard as surfaces that are metal-free.


Scientists as Naturally Obsessed

If you’ve done a Ph.D. in science (or particularly if you’re thinking about it) or if you’re just fascinated with the scientific process, I hope you have an opportunity to see the documentary Naturally Obsessed that chronicles the journey of three graduate students toward the scientific prize in protein crystallography. Only one of them, Robert, wins what most would consider to be the coveted apple– a paper in Science and the pursuit of an academic career. Kil takes his Ph.D. and leaves academia behind for what appears to be a successful career as a consultant for biotechnology and pharmaceutical companies. The third, Gabe, the woman in the group, decides a Ph.D. isn’t what she really wanted and heads back to work as a pharmaceutical researcher. Their adviser, Larry Shapiro at Columbia University, gets tenure.

What I think is so good about the film by former researcher Richard Rifkind and his wife Carole is that it really captures what it’s like to be a developing scientist. And I choose that term deliberately– the process of a Ph.D. is more fundamental than training. It really is developmental.

The film brought me back to my days in the lab (In the end, of course, I’m a female Kil, who took my Ph.D. and jumped off the academic wagon). The three characters reminded me of myself and of the people I worked with. Their struggles reminded me– perhaps a little too clearly, my husband would say– of the highs and lows of the scientific research game. Continue reading Scientists as Naturally Obsessed