Field of Science

Ultimate Death Match: Fungus vs Worm

As the newest penultimate addition to the FoS collective (should any group of bloggers ever use the term collective?), I thought I should introduce myself to the other bloggers here at FoS.

Hi, I'm Lorax. Nice to meet you.

Clearly, I am joining a great group of scientists and am happy to add my ramblings here. However, I am also a competitive jerk. So when I read this cool post over at Skeptic Wonder, where Psi Wavefunction waxes poetic about Theratromyxa, I felt a rush of testosterone course through my veins. Amoeba, like Theratromyxa, are basically just free living macrophage *yawn*. Theratromyxa crawls to their prey (nematodes, which are microscopic worms), engulfs it, and then proceeds to eat the nematode. On the plus side Theratromyxa has two things going for it: 1. A single celled organism eating a multicellular organism is inherently cool, 2. Theratromyxa belongs to a group called the Vampyrellid, I mean that is awesomely cool.
However, if you want a truly amazing nematode hunter, let me introduce you to Drechslerella (previously called Arthrobotrys), a group of filamentous fungi that do something truly amazing! Drechslerella species grow as hyphae (the long spaghetti looking things) and can make spores (there's a collection of 5 cells that formed spores just North of center in the picture). OK, I'll admit that they are not much to look at. And unlike the amoeba, Drechslerella is non-motile, so it needs its food to come to it. If you are hunting prey that moves, but you do not, then you have a problem. Drechslerella deals with this problem in a way analogous to how we catch mice while we sleep, it traps it.

And this is where Drechslerella completely outcools Theratromyxa. I'll let the picture speak for me.
N. Allin and G.L. Barron
The above nematode has crawled into the fungal trap at two points. Along the hypha, a ring is formed by 3 cells. When a nematode enters the ring, these cells rapidly expand (~1/10th of a second) trapping the worm (see below, left and right top two pics). This effectively traps/crushes the worm, think about the last time you stuck your arm in a blood pressure sphygmomanometer (yes that's what those things are called). At this point, cells germinate, sending invasive hyphae into the worm which eats the worm from the inside (see below, right bottom two pics)
This leads to some pretty interesting biological questions. For example, fungal cells are surrounded by a cell wall, how does this expansion occur so quickly? How is the worm detected, are there touch sensors (yes) and do they act like touch sensors in our cells? Are these "trap" cell structures made all the time or only when worms are around? With organisms like this, what does it mean to be multicellular? a differentiated tissue? etc.

Now I should point out that many nematodes are detrimental to plants and biocontrols are sometimes used, including the use of Arthrobotrys (commercially still using the old name).

To conclude: Drechslerella >> Theratromyxa >> Nematodes

UPDATE: Checkout the noob, who bumped me for newest addition. You can learn all kinds of cool things about how the environment affects physiology!


EcoPhysioMichelle said...

Actually I'm the newest addition. ;)

Hello! I don't have an opinion on this debate, since I work with tetrapods. I am fond of planarians, though.

The Lorax said...

Corrected, and Hi.

BTW its not a debate, its a fungal beat down. We'll get to fungal take downs of tetrapods at some point...actually, I touched on bats and geomyces previously :)

EcoPhysioMichelle said...

Are you referring to the white-nose syndrome? I actually know a guy who is doing work on that... and something to do with chestnut blight... although I'll admit I don't really know much of the details of what he does. My knowledge of fungal biology is rudimentary at best.

Lab Rat said...

I'd heard of the fungus trap before, but I'd never seen a picture that awesome before. That's one seriously trapped nematode...

You realize that having thrown down this challenge you might have set off a three-way battle between me you and Psi concerning the respective awesomenesses of bacteria, fungi and protists...

*goes to look up the bacterial-bacteria parasites again*

The Lorax said...

Im up for a friendly little competition, and by friendly I mean, the fungi will win or a kitten gets it.

I will concede that Vampirococcus is a awesome name.

The Lorax said...

EPM - Yes, Im referring to White-Nose Syndrome. The fungus associated with the bats is Geomyces destructans. AFAIK it is still unclear if the fungi are the cause of the problem or a symptom. (I lean toward the latter and wouldn't be surprised to learn a retrovirus is involved.)

Anonymous said...

Ok... I know I am sking for it being a non-scientist and all, but I have a BA from Yale; does that count? but on the serious side, there's something very weird going on in Los Angeles...and I am not talking the date of the Oscars being moved up... several months a friend and I and began separate months-long (their still ongoing) battles with what we thought were large and powerful plasmodial slime molds. To illustrate, this stuff was literally moving walls and terra-forming (I know a sci-fi term) our residences... At the time, I thought if it was a slime mold it wasn't like any I had heard of. My understanding is SM's can grow to the size of several parking lots but are fragile creatures...I feel that this/these organisms are all over Los Angeles, but go easily undected by the naked eye simply because they are very slow moving creatures. It's possible that they are some kind of mold but none that I have read about. My friend and I believe that they were drawn to the moisture in the plumbing system of our separate apt complexes... Since the end of summer their behavior has calmed somewhat but they are still present... I've done a lot of research and the only area of study remotely related to what we've experienced is geomicrobiology. Most of what I found was from Chinese academics and dealt with unrelated issues. What I am now dealing with is a persistent biofilm on the floor of my apt... Most people entering the place would not notice it, but applying certain things such as bleach, ammonia or anything anti-fungal/anti-mold will cause the surface to crack revealing worms embedded in the bio-film... I can go into further detail but if anyone has the slightest clue what the hell this stuff is and how to get rid of it please feel free to contact me at Earlier I did contact a microbiologist at Cal Tech but I never heard back. I only decided to leave this post becuase I stumbled across the thread and you guys seemed to know your microbiology. I would also like to add that for both of us there have been some medical fall out; we are both infected with some which appears as a patch of discolored skin below knees. Mine became infected afetr rollerblading injury. I have also looked into the possibility that we have dermatophytes, but haven't found much info that was helpful. Thanks for your consideration. Spenger Charles, Los Angeles, CA.