"So, naturalists observe, a flea has smaller fleas that on him prey; and these have smaller still to bite ’em; and so proceed ad infinitum."
- Jonathan Swift

September 2, 2010

September 2 - Bdellovibrio bacteriovorus

When I was teaching microbiology, Bdellovibrio was always one of my favorite things to lecture about. These bacteria are essentially intracellular parasites of other bacteria. Bdellovibrio has a rather unusual mode of entering its hosts - it uses its flagellum to crash into them at amazing speeds - 160 um/second (ok, that doesn't sound very fast, but when you're only about 1 micron long, that's hauling!) Once inside its host cell, the Bdellovibrio consumes the nutrients inside it, growing longer and longer the whole time. Eventually, when the host cell has run out of nutrients, the long filament will separate into about 3 to 6 individual cells, lyse the membrane of their former host and go off and infect new victims.


  1. Just wanted to say, I just love the parasite joke on the sidebar.

    My new favourite biology joke!

  2. It is amazing! 2 minutes after I send you a email asking whether you would interested in my work with bdellovibrio, I found this blog. Yes, this hunter bacterium is so unique and interesting. They surprise me all the time...