Photorhabdus: shedding light on symbioses
Unlike the marine environment, bioluminescence in terrestrial bacteria is not yet understood. In this article in Microbiology Today, Susan Joyce and David Clarke describe the complex association between Photorhabdus, its nematode host and their insect prey:
Next time that you are on the beach, walk into the dunes and take a sample of the sandy soil within the area where the dune grass is growing. Place your soil sample in a flask, add a few insect larvae (readily available from your local bait or pet shop) and the chances are good that the insects will be dead within 2–3 days. Take these dead insects into the darkest room in your house and within 5–10 minutes you should see that some, if not all, of the insect cadavers will glow in the dark. This bioluminescence is due to the presence of the bacterium Photorhabdus, a highly virulent insect pathogen (entomopathogen) that you have isolated in a nematode vector from the soil. Together, Photorhabdus and the nematode vector (Heterorhabditis) form a deadly complex that is naturally lethal to insect larvae.
Tags: Bacteria, Microbiology, Parasitology, Science
