Tuesday, June 16, 2009

Oh, beautiful dirt...

Hooray! I am most pleased to be a part of this little blog and plan to mostly post about beautiful contamination, because my other failures are all pretty boring and routine. Soon I will upload a picture of the mold that started it all, a lovely little orange shiny button, which was growing on an LB-Kan plate of mine.

But IN THE MEANTIME...

Behold, something appears to be crystallizing... nearly 30 microns across, you say? Oh but look! They are bicolor... And they are not birefringent. Blasted contaiminating dirt in the crystallography screen getting us all excited for nothing. Ah well.



As you might guess, I am in a protein crystallography lab, and so most of what I will post are from failed adventures in protein expression, purification, and crystallization.

Glossary for the uninitiated:
LB: Luria Burtani broth - a liquid chop full of nutrients for growing up E. coli
Kan: Kanamycin - an antibiotic commonly used in labs to select for the bacteria they want
Plates: It's like making jello out of the LB broth, so that bacteria can grow on the surface
Microns: micrometer, 1/1000,000 of meter, 1/1000 of a millimeter
Birefringent: If something is arrayed in a regular matrix, like in a crystal, and has directionality to it (like is a large blobby protein), it can bend light. Therefore, if youre shining polarized light at it, and look at it through a polarized lens, it will light up when the rest of the light is canceled out by the polarization...
Crystallography: this is when us biochemists try to crystallize things like large biomolecules to make crystals, not unlike salt or rock crystals. The molecules are arranged in giant regular arrays and make crystals, which are actually very fragile. Then we can shine x-rays on them, and from the light patterns that result, determine a three-dimensional structure of the protein. The idea is that if there are LOTS of protein molecules all arranged the same, their composite signal will be MUCH stronger than if there were just one protein bouncing light around.
Protein expression and purification: We enslave bacteria to grow protein for us, and then we kill them and take all their protein through extensive purification processes so that we only have the one kind of protein we want left. Things need to be especially pure for crystallography purposes because we don't want impurities in our crystals. PERFECTION!

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