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Tuesday, September 29, 2009

Monday's Molecule #138: Winner

The purple molecule is cyclin bound to phospho-cyclin-dependent kinase 2 (CDK2) (yellow) and kinase-associated phosphatase (KAP) (blue). The Nobel Laureate is Tim Hunt.

There were lots of correct answers from Asia and Europe this time around but also a few from North America.

This week's winner is Joshua Johnson of Victoria University in Australia. The posting time was convenient for Australians since his email message was sent at 2 o'clock in the afternoon. There wasn't an undergraduate winner this week so I'll carry over the undergraduate prize for next week's molecule.

This is the earliest posting of a Monday's Molecule. It should make the contest open to a whole new category of Sandwalk readers, especially those in Europe who will see it long before the readers in North America are awake.

It will also work for Asian readers and a few North and South Americans who are up very late at night. (Note to the latter group: get a life! )

The molecule is a compex of three different proteins. One of them—the yellow one—has already been featured as a Monday's Molecule last April. This time I want you to identify the purple molecule. It was first identified and characterized in the organism shown below then subsequently found in lots of other species.

The Nobel Laureate from last April shared the prize with the person who discovered today's molecule. Name that Nobel Laureate.

The first person to identify the molecule and name the Nobel Laureate wins a free lunch. Previous winners are ineligible for six weeks from the time they first won the prize.

There are only three ineligible candidates for this week's reward: Philip Johnson of the University of Toronto, Ben Morgan of the University of North Carolina at Chapel Hill and Frank Schmidt of the University of Missouri.

Frank has agreed to donate his free lunch to a deserving undergraduate. Consequently, I have an extra free lunch for a deserving undergraduate so I'm going to award an additional prize to the first undergraduate student who can accept it. Please indicate in your email message whether you are an undergraduate and whether you can make it for lunch. If you can't make it for lunch then please consider donating it to someone who can in the next round.


Nobel Laureates
Send your guess to Sandwalk (sandwalk (at) and I'll pick the first email message that correctly identifies the molecule(s) and names the Nobel Laureate(s). Note that I'm not going to repeat Nobel Prizes so you might want to check the list of previous Sandwalk postings by clicking on the link in the theme box.

Correct responses will be posted tomorrow.

Comments will be blocked for 24 hours. Comments are now open.


DK said...

But I answered correctly a day earlier than the winner :-) Time zones. You know they are a good thing...

charlie wagner said...

Conjugative plasmids: vessels of the communal gene pool

1. Anders Norman*,
2. Lars H. Hansen and
3. Søren J. Sørensen

+ Author Affiliations

Department of Biology, Section for Evolution and Microbiology
, University of Copenhagen,
Sølvgade 83H, 1307 Copenhagen K
, Denmark

1. *Author for correspondence (


Comparative whole-genome analyses have demonstrated that horizontal gene transfer (HGT) provides a significant contribution to prokaryotic genome innovation. The evolution of specific prokaryotes is therefore tightly linked to the environment in which they live and the communal pool of genes available within that environment. Here we use the term supergenome to describe the set of all genes that a prokaryotic ‘individual’ can draw on within a particular environmental setting. Conjugative plasmids can be considered particularly successful entities within the communal pool, which have enabled HGT over large taxonomic distances. These plasmids are collections of discrete regions of genes that function as ‘backbone modules’ to undertake different aspects of overall plasmid maintenance and propagation. Conjugative plasmids often carry suites of ‘accessory elements’ that contribute adaptive traits to the hosts and, potentially, other resident prokaryotes within specific environmental niches. Insight into the evolution of plasmid modules therefore contributes to our knowledge of gene dissemination and evolution within prokaryotic communities. This communal pool provides the prokaryotes with an important mechanistic framework for obtaining adaptability and functional diversity that alleviates the need for large genomes of specialized ‘private genes’.

Now let's see...where have I heard that before?

"You use the phrase "producing lots of information from very simple nucleotide changes". This suggests to me that you're not "producing" the information, but you're simply activating already existing potential.
Which again begs the original question: what is the origin of this potential? Might not all of the potential be present in the gene pool and might it not have been there from the very beginning?" (, Aug 8, 2000)

charlie wagner said...

Maybe in eukaryotes too? Huh?