Monday, July 9, 2007
Summertime Light
I'm back after a bit of an absence. Summer has been very busy and I did take a little time to head back to my home state of Michigan for some camping. One thing I rediscovered was the joy of fireflies. We don't have them where I live now, but I remember the lazy late summer days of my youth chasing and catching these wonderful creatures. They are out in force this year glittering and lighting up the summer nights. Of course this leads to chemistry and not just nostalgic blatherings. As a kid I was fascinated by how the light was produced and we owe it all to a little molecule called Luciferin. In the presence of Luciferase and ATP, an AMP-modified luciferin is produced. This, in turn, reacts with oxygen to produce oxyluciferin in the excited state. Relaxation to the ground state produces the all too familiar orange-yellow glow of the firefly. Nature comes up with some unique ways for males to attract mates, and this is one of the more interesting ones.
Subscribe to:
Post Comments (Atom)
11 comments:
This is neat! I always wanted to know but never got around to look it up.
Luciferin...does it has anything to do with Lucifer? Anyway, we have the little firefly over here too. Have you try catching a few fella in a jar? It will actually light up your tent. Be sure to let it go afterward! Sad to say, there are not many left. Development, forest clearing, pollutions ... every year, they are getting fewer in numbers.
Actually, the name does come from lucifer.
Lucifer |ˈloōsəfər| noun
1 another name for Satan .
2 poetic/literary the planet Venus when it rises in the morning.
3 ( lucifer) archaic a match struck by rubbing it on a rough surface.
ORIGIN Old English , from Latin, ‘light-bringing, morning star,’ from lux, luc- ‘light’ + -fer ‘bearing.’
Not only is it used by males to attract mates ("look honey, my butt lights up!"), but it is also used by some females to attract males for food.
Mmmmm...
I too miss fireflies (and Firefly as well ;))
Where in Michigan? I'm a Yooper by birth and upbringing. We have no fireflies, or aurora borealis, in New England. There is a lot about home i miss, and those two are very high on the list.
Well, I grew up near Kalamazoo and was down near Sturgis camping. But my father is from Calumet. I love the Keewenau. I still make my grandmother's pasty recipe. We camped up at Fort Wilkins a few years ago. That as wonderful.
Hey...what's "pasty"? Care to share the recipe?
Hmm, do the fireflies excrete oxyluciferin as waste, or is it recycled?
Good question. It looks like there is an enzyme called 'Luciferin Regeneration Enzyme'. You gotta love the descriptive biochemistry nomenclature. Anyway, the enzyme cleaves off thioacetic acid to produce a benzothiazole bearing a cyano group. Then, in a second step, cysteine is added to regenerate luciferin.
Read more in this JBC article:
http://www.jbc.org/cgi/content/abstract/M105528200v1
Hey, I've just read recently published Shimomura's "Bioluminescence". You should call the compound "firefly luciferin", there are more luciferins. I plan a post on it. :)
Greg, I did it!
http://liquidcarbon.livejournal.com/10030.html
Post a Comment