Monday, April 29, 2013

Monday's Molecule #203

The last Monday's Molecule was medium chain acyl-CoA dehydrogenase (MCAD) (PDB 2AIT). Nobody got the right answer [Monday's Molecule #202].

Today's molecule is very important for humans. You need to supply the common name AND a more official IUPAC name that identifies the configuration of the bonds. You also need to briefly explain why this molecule is important in humans.

Email your answers to me at: Monday's Molecule #202. I'll hold off posting your answers for 24 hours. The first one with the correct answer wins. I will only post mostly correct answers to avoid embarrassment. The winner will be treated to a free lunch.

There could be two winners. If the first correct answer isn't from an undergraduate student then I'll select a second winner from those undergraduates who post the correct answer. You will need to identify yourself as an undergraduate in order to win. (Put "undergraduate" at the bottom of your email message.)

Some past winners are from distant lands so their chances of taking up my offer of a free lunch are slim. (That's why I can afford to do this!)

In order to win you must post your correct name. Anonymous and pseudoanonymous commenters can't win the free lunch.

Winners will have to contact me by email to arrange a lunch date. Please try and beat the regular winners. Most of them live far away and I'll never get to take them to lunch. This makes me sad.

Comments are now open.

UPDATE: The molecule is linolenate, also known as α-linolenate. (There's another common linolenate called γ-linolenate. It has double bonds in the 6,9, and 12 positions.) The official IUPAC name is (9Z,12Z,15Z)-octadeca-9,12,15-trienoate. Other common names are all-cis-9,12,15-octadecatrienoate, all-cis-9,12,15-linolenate, all-cis9,12,15-linolenate, or simply 18:3 Δ9,12,15. Linolenate is an omega-3 fatty acid because it has a double bond at at the third carbon from the end. (Omega is the last letter of the Greek alphabet and it identifies the last carbon in a fatty acid.) Linolenate is an essential fatty acid in human diets because we have lost the ability to synthesize it. (We lack a desaturase that acts beyond the 9 position.) Linolenate and linoleate are required as presursors for synthesis of other essential molecules such as arachidonate and prostaglandins.

Note that the molecular shown is linolenate, the conjugate base of linolenic acid. It is NOT the acid.

The winner is Anders Ehrnberg.

Nov. 2009: Jason Oakley, Alex Ling
Oct. 17: Bill Chaney, Roger Fan
Oct. 24: DK
Oct. 31: Joseph C. Somody
Nov. 7: Jason Oakley
Nov. 15: Thomas Ferraro, Vipulan Vigneswaran
Nov. 21: Vipulan Vigneswaran (honorary mention to Raul A. Félix de Sousa)
Nov. 28: Philip Rodger
Dec. 5: 凌嘉誠 (Alex Ling)
Dec. 12: Bill Chaney
Dec. 19: Joseph C. Somody
Jan. 9: Dima Klenchin
Jan. 23: David Schuller
Jan. 30: Peter Monaghan
Feb. 7: Thomas Ferraro, Charles Motraghi
Feb. 13: Joseph C. Somody
March 5: Albi Celaj
March 12: Bill Chaney, Raul A. Félix de Sousa
March 19: no winner
March 26: John Runnels, Raul A. Félix de Sousa
April 2: Sean Ridout
April 9: no winner
April 16: Raul A. Félix de Sousa
April 23: Dima Klenchin, Deena Allan
April 30: Sean Ridout
May 7: Matt McFarlane
May 14: no winner
May 21: no winner
May 29: Mike Hamilton, Dmitri Tchigvintsev
June 4: Bill Chaney, Matt McFarlane
June 18: Raul A. Félix de Sousa
June 25: Raul A. Félix de Sousa
July 2: Raul A. Félix de Sousa
July 16: Sean Ridout, William Grecia
July 23: Raul A. Félix de Sousa
July 30: Bill Chaney and Raul A. Félix de Sousa
Aug. 7: Raul A. Félix de Sousa
Aug. 13: Matt McFarlane
Aug. 20: Stephen Spiro
Aug. 27: Raul A. Félix de Sousa
Sept. 3: Matt McFarlane
Sept. 10: Matt Talarico
Sept. 17: no winner
Sept. 24: Mikkel Rasmussen
Oct. 1: John Runnels
Oct. 8: Raúl Mancera
Oct. 15: Raul A. Félix de Sousa
Oct. 22: Mikkel Rasmussen
Nov. 12: Seth Kasowitz, Bill Gunn
Nov. 19: Michael Rasmussen
Dec. 4: Paul Clapham, Jacob Troth
Dec. 10: Jacob Troth
Dec. 17: Bill Chaney, Dima Klenchin, Bill Gunn
Jan. 14: Evey Salara
Jan. 21: Piotr Gasiorowski
March 11: Bill Gunn, River Jiang
March 18: Bill Gunn
April 8: Michael Florea
April 15: no winner
April 29: Anders Ernberg


  1. People who correctly identified the molecule:

    Brian Shewchuk

    People who correctly identified the molecule and explained why it is important.

    "Buddha Buck" (anonymous, disqualified)
    Anders Ehrnberg (winner)
    Bill Chaney
    Black_Rose (ID known to me)
    Bill Gunn

  2. My apologies to Buddha Buck. That's his real name.