Saturday, December 24, 2011

BacterioFiles Micro Edition 68 - Crustacean Calorie Caretaker

Credit: Oregon State University
This episode: Newly-discovered underwater crab farms its own bacterial food!

Download Episode (2.9 MB, 3 minutes)

Show notes:
News item 1/News item 2/Journal Paper


  1. Great to hear about this fantastic symbiosis. When crustaceans ecdyse (moult), they shed their exoskeleton. What happens to the bacterial population of the setae during this phase? Do the animals have a behaviour to repopulate the newly grown exoskeleton?

  2. Good question! I would guess that some bacteria might transfer to the new exoskeleton during the ecdysis process, or maybe the new exoskeleton is colonized by free-swimming bacteria or by some shed by the crabs nearby. Here is what a paper on a related crab species said on the topic:

    "Many questions remain regarding this and other crustacean–epibiont associations. How is the bacterial community transferred and re-grown following ecdysis by the host? Recently molted barnacles (Lau sp. A) have fewer filamentous bacteria on their setae than those nearing ecdysis (Southward and Newman, 1998). Similarly, larval copepods have fewer bacterial epibionts than adults that completed a terminal molt (Carman and Dobbs, 1997). Recolonization after molting may be facilitated by a few residual bacteria, or perhaps by recognition of the host surface by new free-living forms of the bacteria. Recognition and binding of epibionts on two nematode species, which also undergo ecdysis, were shown to be mediated by host lectin binding to mannose and rhamnose residues on the symbiont (Nussbaumer et al., 2004; Bulgheresi et al., 2006). Although it is not known how the epibionts attach to K. hirsuta, the presence of a putative exopolysaccharide substance on the setae and surrounding the epibionts may facilitate attachment."
    The full paper is here: