Category → Chemistry Comes Alive
How Would You Explain pH to First-Graders?
So, this was the dilemma I encountered this week at the day job.
In my position at the North Carolina Museum of Natural Sciences in Raleigh, we give public “Meet the Scientist” talks twice daily in our iconic multimedia space called the SECU Daily Planet in the new Nature Research Center wing of the Museum. The Daily Planet Theater seats about 50 folks on the main floor but is open on part of the 2nd and 3rd floors for visitors to peer into events there.
The SECU Daily Planet, Nature Research Center, North Carolina Museum of Natural Sciences, Raleigh, NC. Photo: Robert Carpenter, NCMNS Flickr
Must-See ACS Webinar: Superbugs and Drug Development
SUPERBUG author, Maryn McKenna.
One of science journalism’s expert voices, author Maryn McKenna, will be the guest on this Thursday’s ACS Webinar Joy of Science series at 2:00 – 3:00 pm Eastern time.
Free, as always, you can sign up to participate at this link.
McKenna’s book, SUPERBUG: The Fatal Menace of MRSA, is a thorough and accessible investigation of the reemergence of lethal bacterial infections while new drug development lags.
The book, now in paperback, received the 2011 Science in Society Award from the the National Association of Science Writers.
McKenna had spent much of her career at the Atlanta Journal-Constitution as the only U.S. reporter assigned full time to the Centers for Disease Control and Prevention. In fact, her first book, Beating Back the Devil, detailed her experiences with CDC’s Epidemic Investigation Service (EIS), the team dispatched anywhere in the world that’s experiencing an unusual infectious disease event.
From her book’s website:
I was following a group of disease detectives from the Centers for Disease Control and Prevention, the CDC, through an investigation of bizarre skin infections in Los Angeles. The CDC wanted to know where men were picking them up. I wanted to know something more fundamental: How could a minor problem — something that the victims all described as looking like a tiny spider bite — blow up into massive infections that ate away at skin and muscle, put people into the hospital for weeks and drained their health and their bank accounts? Where had it come from? And if it could do that, what else was it capable of?
A multidrug-resistant Staphylococcus aureus (MRSA) plushy from GiantMicrobes.com, personalized for the author by Maryn McKenna. Photo credit: DJ Kroll
Maryn’s one of the best science writers in the world in terms of mastering her subject and making it widely accessible.
Of course, her webinar will be of interest to anyone concerned about the proliferation of drug-resistant infectious diseases and how to design drugs to stay a step ahead of evolution.
But she’s also a great model to emulate for anyone trying to make their scientific work more approachable to non-experts. You might even learn a thing or two about telling a gripping story.
And, thanks to your American Chemical Society, dialing into the webinar is FREE. Go here to register.
You don’t even need to be an ACS member!
You can thank me later.
The webinar will be archived but you can also hear from Maryn McKenna on a regular basis at her Wired Science blog, Superbug and on Twitter @marynmck.
Why Isn’t Caffeine Called “Theoanaleptine”?
This question came to me as I read last week’s C&EN cover story by Dr. Lauren K. Wolf on caffeine toxicity entitled, “Caffeine Jitters.”
By the way, read it if you haven’t — it’s open-access on C&EN right now and remains the most-read (last 7 days), most-commented (last 30 days), and most-shared (last 30 days) article since it appeared. Lauren did a terrific job of sifting through decades of information on the physiological effects of caffeine to make sense out of the true health hazards of caffeine consumption at “normal” and excessive doses.
Caffeine, a natural alkaloid found predominantly in coffee beans, is 1,3,7-trimethylxanthine (not IUPAC, but you get it). In the body, the hepatic cytochrome P450 CYP1A2 catalyzes the N-demethylation of caffeine to theophylline, theobromine, and paraxanthine.
The cytochrome P450 CYP1A2 catalyzes the N-demethylation of caffeine to one of three dimethylxanthines, with paraxanthine predominating. Credit: C&EN
Divine chemicals
Of note, theobromine and theophylline also occur in nature. Theobromine is found in cacao beans. Because chocolate is heavenly, it was given the Greek name for “food of the gods”: theos – god; broma – food.
Correct, theobromine contains no bromine. Had it contained bromine, the name might have been the same but would have been derived from the Greek bromos, or “stench” – “stench of the gods,” which, clearly, it is not.
Stimulant of the Gods. Available now at the Pharmacopolis store at Zazzle.
Theophylline also occurs naturally and had been extensively used as a bronchodilator for folks with asthma. Primatene tablets used to contain theophylline but today are ephedrine. Again, theophylline has the godly theo- prefix while the -phylline suffix indicated that it comes from leaves.
And apologies to paraxanthine. It’s known historically for having first been isolated from urine in 1883. Not until the 1980s was it shown to occur in some plants. In any case, the biosynthesis of the di- and tri-methylxanthines originate with xanthosine from purine metabolism.
So to my question. . .
Because caffeine is so widely worshiped, why is it not known as theoanaleptine? The Greek analeptikos means stimulant and the English term analeptic is defined as a stimulant drug.
So, why not?
My best guess is because caffeine was described in the literature prior to theophylline and theobromine. From M.J. Arnaud’s chapter in Caffeine (Springer, 1984):
The isolation of caffeine from green coffee beans was described in Germany in 1820 by Runge and confirmed the same year by von Giese. In France, Robiquet in 1823 and then Pelletier in 1826 independently discovered a white and volatile crystalline substance. The name “cofeina” appeared in 1823 in the “Dictionaire des termes de medécine” and the word “caffein” or “coffein” was used by Fechner in 1826.
Arnaud goes on to say that theobromine was discovered in cocoa beans in 1842 and theophylline in tea leaves in 1888.
So, caffeine had about a two-decade headstart in being named for its presence in coffee before related methylxanthines took on their divine monikers.
Sure, sure, caffeine is a well-recognized name that derives predictably from its source. But let’s live a little. Wouldn’t you rather be drinking the stimulant of the gods?
If you’re as excited about this as I am, you may purchase theoanaleptine coffee mugs here. They’ll set you apart from ever Tom, Dick, and Harriet who think they’re clever with their caffeine coffee mugs.
And even with accepting the new colloquial name of theoanaleptine, our friend Scicurious can still keep her tattoo unchanged.
Video: Why Do Leaves Change Color?
Rob Nelson is an independent science education filmmaker now living in Charlotte, NC, with his equally talented wife, Haley, and their son. Together with his partner in Sweden, Jonas Stenstrom, Rob runs a company called Untamed Science.
I first met Rob through my new position at the North Carolina Museum of Natural Sciences when he made a video introducing all of our new research laboratory directors.
In the video posted here, he addresses the biology and chemistry (!) of leaves changing color in the fall together with my boss, Meg “Canopy Meg” Lowman, Director of the Museum’s Nature Research Center. It’s a catchy introduction to the chemistry behind color change. Enjoy!
HHMI and Duke Celebrate the Lefkowitz Chemistry Nobel
As discussed in my previous post, I took a personal day off from work yesterday to bask in the excitement of a university community celebrating a Nobel prize for one of its most beloved researchers, Dr. Robert “Bob” Lefkowitz, MD. He joined Duke in 1973 when, he says, “it was not the powerhouse it is today.”
Lefkowitz will share the prize with his former trainee, Brian Kobilka, MD, now at Stanford University.
I had the honor of joining his laboratory’s champagne celebration in the morning and the Duke University press conference in the early afternoon. (The full 47-minute press conference streamed live and is archived here at Duke.).
I live barely three miles from Duke and had no idea when or if I’d ever have the chance to be so close to such an event. The Lefkowitz prize is particularly meaningful to me as he is a biochemist physician-scientist who also considers himself a pharmacologist. So, I write this not so much as a journalist but rather — as Duke Research Communications Director Karl Leif Bates put it — a fan boy.
Lefkowitz and Kobilka win 2012 Chemistry Nobel for GPCRs
Defending the Chemistry Nobel for “biology” – again.
I’m near-certain that this is the first Nobel Prize in Chemistry given to two MDs. (10:31 am EDT: I was wrong, as per commenter Jonny below. Peter Agre, MD, and Roderick MacKinnon, MD, received the Nobel Prize in Chemistry 2003 for their work on aquaporins and other ion channels.)
Robert Lefkowitz, MD, of the Howard Hughes Medical Institute and Duke University Medical Center, and Brian Kobilka, MD, of Stanford University School of Medicine, will share the Nobel Prize in Chemistry 2012. The award recognizes a lifetime of work, certainly for Lefkowitz, in elucidating the action of the central chemical signal transducers of the human body.
This is a chemistry prize, albeit a biological chemistry prize.
The prize is being given for discovering how the body’s most important chemicals communicate their own chemical signals from outside the cell to inside. Without G-protein-coupled receptors, or GPCRs, our hearts would not beat, our lungs would not expand and contract, and our brains would be unable to regulate much of everything that runs in our bodies.
Moreover, the ubiquity of GPCRs have over history breathed tremendous life and stimulated innovation in chemistry to synthesize tools to modulate these receptors and thereby relieve human suffering. Chemists should revel in this prize – without G-protein coupled receptors, many chemists would not have been employed for the last few decades.
But I do agree that a case could be made for this prize to be given in Physiology or Medicine, particularly since GPCRs are central to physiology, “from plants to man.”
More later.
Feel free to vent your spleen in the comments below.
But do note that Derek Lowe, medicinal chemist and grand master of the chemblogosphere, has already decreed, “[M]y fellow chemists, cheer the hell up already.”
Disclosure: I hold an Adjunct Associate Professor appointment in the Duke University School of Medicine, Department of Medicine.
Gurdon and Yamanaka share Nobel Prize in Physiology or Medicine 2012
British scientist John B. Gurdon and Shinya Yamanaka (MD, PhD!), a Japanese scientist now at the Gladstone Institutes in San Francisco, were awarded the Nobel Prize in Physiology or Medicine this morning, ”for the discovery that mature cells can be reprogrammed to become pluripotent.”
John B. Gurdon. Credit: nobelprize.org, Creative Commons Attri 2.0 license.
Briefly, Gurdon and colleagues showed that the genetic information from a mature, differentiated cell still had the ability to program an undifferentiated embryonic cell to develop into an adult organism. That is, an embryonic cell contains the chemical signals to use adult DNA to drive development of a new organism.
The work was done with the frog, Xenopus laevis, and the technique came to be known as “nuclear transfer.” In colloquial terms, this is “cloning.” Current press reports are citing Gurdon’s work as occurring in 1962 but studies appear to have been published in Nature as early as 1958.
Christen Brownlee composed a superb summary of nuclear transfer for the Classics section of the Proceedings of the National Academy of Sciences. Gurdon’s work stemmed from 1952 experiments of Robert Briggs and Thomas J. King with another frog, Rana pipens. Briggs died in 1983 and King in 2000 and could not be recognized with the Nobel. This fact relieved the Nobel committee, in my opinion, from having to decide which scientist would have been awarded the potential third slot for the prize. (Addendum 7:18 am EDT): I suspect that some argument will arise in support of UW-Madison’s James A. Thomson for the third slot as the Science paper from his group came out concomitantly with Yamanaka’s Cell paper. 8:21 am: The Guardian’s Alok Jha just reminded me that I overlooked Takahashi and Yamanaka’s earlier Cell paper from 2006. However, C&EN’s Carmen Drahl is now reporting this 2001 TIME magazine cover with Thomson.)