Photorhabdus luminescens act as an accomplice to a tiny worm called a nematode. The nematode totes the bacteria around in its gut until it finds a suitable victim, such as a fat caterpillar.
Scientists are not sure about the purpose of the P. luminescens’ glow. There is a suitably grim possibility: it may be ordering its next meal. Living insects might be drawn in by the light, only to meet a horrific fate.
HOW DOES IT WORK?
It worms its way into the insect’s bloodstream, then spits up the bacteria. P. luminescens spew toxins that kill the insect, enzymes that liquefy it, and antibiotics that prevent any other microbes from getting in on the feast. The worm and bacteria reproduce inside the carcass until finally new nematodes burst forth.
WHY SYNTHESIZE THIS?
P. luminescens can get into human wounds, but they usually do not cause disease. In fact, having a wound that glows ghastly green is a good sign for recovery.
During the American Civil War, soldiers called it the “Angel’s Glow”. Presumably, the antibiotics P. luminescens can ward off freeloader microbes as well as keep the wound clean.
Image: Dead moth grub infected by the Photorhabdus Luminescens, by Dante Fenolio.