Monday's Molecule #61

 
Today's molecule is three molecules. You have to identify the purple molecule on the left and the blue one near the top. You also have to identify the multicolored double-stranded helically thing that's holding them all together. (Hint: it's DNA.) The electron micrographs at the top serve as additional hints.

You have to give me the common names of these molecules and explain what's going on in the figure. You'll be pleased to know that I don't need the systematic IUPAC name for this one. This should be as easy as falling off a log for every biochemistry and molecular biology student but I fear that it may fall into the category of things that have been forgotten in modern courses.

There's an indirect connection between this molecule and Wednesday's Nobel Laureate(s). Your task is to figure out the significance of today's molecule and identify the Nobel Laureate(s) who worked with it. Here's an additional hint for this week only; I'm looking for a single name and if you can't decide between two or more possibilities, choose the earliest winner. (Be sure to check previous Laureates.)

The reward goes to the person who correctly identifies the molecule and the Nobel Laureate(s). Previous winners are ineligible for one month from the time they first collected the prize. There are three ineligible candidates for this week's reward. The prize is a free lunch at the Faculty Club.

THEME:

Nobel Laureates
Send your guess to Sandwalk (sandwalk(at)bioinfo.med.utoronto.ca) and I'll pick the first email message that correctly identifies the molecule and the Nobel Laureate(s). Note that I'm not going to repeat Nobel Laureates so you might want to check the list of previous Sandwalk postings.

Correct responses will be posted tomorrow along with the time that the message was received on my server. I may select multiple winners if several people get it right.

Comments will be blocked for 24 hours. Comments are no open.

UPDATE: No winner this week. There were (only) three people who got the molecule correct. Only one of them was close to getting the Nobel Laureate (singular). That person named him correctly (François Jacob) but he threw in a second Nobel Laureate who had already been featured on Sandwalk.

The molecule is lac repressor bound to two sites on DNA forming a loop. The loop contains the binding site for cyclic AMP regulatory (receptor) protein or CRP, also known as catabolite activator protein (CAP). That's the other protein in the figure. The figure is from Lac Repressor and Operator.

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