I am a luminescent freak
23 Juillet 2003
I have strange hobbies. At least, that's what people often tell me. It's just because I have a genuine fascination for very different things, so I often collect them and make them myself when it's possible. I collect art holograms and once transformed my appartment into an holography studio with several kinds of lasers. I did some calligraphy, and so I collected medieval calligraphied manuscripts. I love robotics, so I constructed several small size, insect-like robots that wandered around my appartment. I always was fascinated by anything that can fly, so I have a few boomerangs, a radio-controlled flying saucer, and practiced hand-gliding a long time ago. All of these hobbies come and go in a cyclic manner, but they are always present somewhere in my mind. For a few months I just think about it a lot, I buy different tools, I read everything on the subject, I learn techniques, I make stuff, and then one day I put everything back in big boxes until the envy comes back, sometimes years later.
I already listed a few of my weird hobbies. Here is another one: I'm fascinated by bioluminescent organisms. Living things that emit light. I remember once, in Manhattan's Central Park at night, hundreds of fireflies moving around, it was wonderful, so beautiful. Or, when I was a kid and we went at night on the beach, sometimes there were these luminescent algae, which glowed when you agitate the water, not very bright, but enough to be able to spot a friend swimming a couple hundred meters from the shore. Small dots of lights in my beloved Mediterranean that flash so quickly that it's difficult to catch each individual one, even if you really try hard to look at them. It gives the halo of light a sort of unreal, ethereal dimension.
A few weeks ago, I was reading some nice web pages about this, most notably Luxgene, this page in Poland and The Bioluminescence webpage, all done by fellow scientists with the same fascination, and it suddenly came to my mind that nowadays you can buy anything through the internet. Even living organisms. And there should be no problem growing them, after all, I'm a biologist. I could create transgenic luminescent or fluorescent organisms in my lab (I actually do that often - fluorescence is a nice tool to track proteins), but it's more magical when it's all natural.
So I ordered various things. Two different strains of seawater bacteria: Photobacterium phosphoreum and Vibrio fisheri. Spores of a fungus which fruiting bodies (also called mushrooms) are luminescent: Panellus Stypticus. And the very same photosynthetic algae (dinoflagellates family) that I could see in the Mediterranean: Pyrocystis fusiformis (and, incidently, reach an incredibly high concentration in a particular bay in Puerto Rico).
And now I'm growing all of them. It's fun. I will probably dedicate an entire page to that when I have enough pictures (natural luminescence is a bitch to photograph, by the way). Right now, let's have a look at a few pictures of luminescent bacteria from my collection growing on Petri dishes. On the left are Photobacterium phosphoreum (now renamed Vibrio phosphoreum). On the right, Vibrio fisheri. Technical side-note: they are grown on an agar BOSS medium in the dark at room temperature. The pictures shown here were taken 18 hours after spreading on agar bacteria from a frozen 10% glycerol stock kept at -80°C.
Notice the subtle color difference between both strains, one being more blueish, and the other one more greenish. Beautiful, no?