
Fastest Spring in Nature: Vorticella! Don’t blink now , but what you see as a graceful drifting up of the champagne-glass like body actually comes after an incredibly rapid contraction (~5 milliseconds) of the stalk. For its size, Vorticella convallaria is one of the fastest moving organisms on the planet.
What is this? Vorticella is a protozoan that attaches to solid objects (here, a layer of algae) through extremely strong natural adhesives. The 40 μm body is held up by a 150 μm long stalk.
How do they do this? Inside the stalk is a contractile spring, called the spasmoneme, which rapidly winds helically in response to binding calcium. The calcium signal is propagated down the stalk as a wave, after release from the body. This is similar to a muscle contraction, except that Vorticella is 10 times faster.
How fast is it? Contraction speed is estimated at 10 cm s−1. Expressed in units of lengths per second (Ls−1) (standard for muscle contraction), this works out to around 200 Ls−1. This speed is an order of magnitude faster than the fastest muscles, which contract at around 20 Ls−1. The tensile force is up to 500 nNewton. Young’s modulus of the stalk is around 1 kPa.
Why do they do this? Contraction is a defense mechanism to protect Vorticella from environmental hazards such as turbulent water.
♫ Music for Science ♫: Konstantin Makov suggests listening to The Beatles – Maxwell’s Silver Hammer (2009 Stereo Remaster) while you marvel at Nature’s fastest spring. Is Maxwell pounding on the little heads with an invisible hammer? Thank you, Konstantin, for being funny and clever as always.
Fastest Gif-er on G+: Thank you Kevin Staff for being tolerant of my requests and obliging me for #ScienceSunday once again!
Read more: Don’t blink: observing the ultra-fast contraction of spasmonemes. Marshall WF. http://www.ncbi.nlm.nih.gov/pubmed/17933874
You have the magical ability to outdo yourself on a regular basis, Rajini Rao !!
Actually, Gregory Esau , Nature regularly outdoes herself and I’m simply trying to keep up as an appreciative curator! Thank you 🙂
Another outstanding post! Thank you!
Touche, Rajini Rao !!!!
Interesting!, but it almost seems the movement is more potentially damaging than any turbulent water could be!
The whole group of peritrichs (stalked ciliates) is too cool.
Bill DeWitt , what is interesting is that the head barely rotates despite the rapid helical contraction of the spring. So this is like us snatching our finger away from a burn. It’s also quite energy conserving..the contraction can repeat several times even without ATP.
Is it known what triggers the calcium itself?
Michael Griffith , calcium is released from stores through a process called “calcium induced calcium release”. An initial trigger most likely electrical, causes (voltage activated) calcium channels to open. A little bit of calcium is sensed by ion channels which open to release even more calcium. It’s like opening a flood gate so that a large amount of calcium is quickly released. The calcium binds to proteins called spasmins (related to centrins in our cells that are involved in chromosome movement during cell division and steering of cilia), and this somehow causes contraction of the central fiber.
Sounds like those false “free energy” machines they make on Youtube where you turn over one magnet and all the rest turn over. Electron imbalances on one side of a coil maybe transmitting their imbalance down the line? Probably most of the work is done in relaxing the coil.
Bill DeWitt : I’m not sure what is known about the actual contractile machinery here (plenty is known about muscle contraction, on the other hand..due to actin and myosin). The first link I provided does some speculating. This is not exactly a hot bed of research 😉 ATP is required to sequester the calcium after release, by energy dependent pumps (my favorite molecules).
For published work, Howard E. Buhse, Jr at UIC published on spasmins in 2000 and some newer studies were looking at biophysics of spasmins (at MIT as I recall around 2008-9).
Any idea of how often they can do this?
I have not done work to clock them (they are too fast) but they, if you keep annoying them with a probe, etc. will do it repetitively.
Brian Mahon , thanks for the information. Buhse’s group has cloned the calcium binding protein, spasmin, which has the characteristic EF hand motif that binds calcium, similar to mammalian centrins. Do you work on these critters then? I read somewhere that the relaxation is in the order of a couple seconds, so that must limit the frequency of contraction, Michael Griffith .
I played with them when I could find them when I was a postdoc in the Zufall lab at University of Houston (Evolution of Developmental Genome Rearrangements in Ciliates). I was interested in the whole group of peritrichs and evolution of spasmins in the group. There are two different contractile patterns in the group and some lack stalks others are colonial.
I would say the time between contractions is fairly short, a second or two but I was not timing it and working on small patches attached to debris and aquatic insect exoskeletons. They are hard to see individuals and it has been over 4 years since I had any to poke at.
Stuff like this really makes me want to trade in my computer administration hat for a biological sciences hat.
Interesting ~
cue bugs bunny music.
Try Maxwell’s Silver Hammer instead, james kalin 🙂
Thank you for sharing this! It never ceases to amaze me how much variety and wonder there is in the biological world.
+Rajiji Rao Another one of those great posts.
For me, there is no beauty like the beauty of nature just doing its thing, captured so nicely in this clip. Wow.
Very Nice…
Geez Rajini you continually boggle my mind! Thank you so much dear friend.
I’ve been ill for a few days, so I have fallen far behind.
Rajini Rao Any idea if they fire in some coordination? A group at a time?
In the Video, it looks like that….
mandar khadilkar , my guess is that the clustered zooids are all responding to the same perturbation in their local environment. Also, one Vorticella contracting could itself cause enough of a disturbance to trigger the other contractions (since the contraction is so fast, our eyes probably cannot distinguish which one goes first). Other than that, since these are independent organisms and not physically connected, I doubt that they are communicating with each other.
Makes sense. Thx
Aww, thanks Feisal Kamil . I’m having fun digging these out.
I’ve seen some of the episodes..checking them out, thanks.
Funnily enough, Feisal Kamil , I knew the answer to the obscure question in that episode (who named the first world war) you posted because it was in the trivia included in my post on Ernst Haeckel: https://plus.google.com/114601143134471609087/posts/BSaPr2nm6XZ
It’s also remarkable to me that the contraction is triggered by the flow of calcium ions. Curious how nature seems to gravitate towards similar mechanisms to implement a range of fast processes.
Matt Kuenzel , great observation! Ca2+ ion is a universal second messenger in biology. Because it is an element, calcium need not be synthesized nor broken down enzymatically. It can be rapidly moved in and out of compartments by pumps and transporters (uphill) or channels (downhill). The kinds of signaling events that calcium mediates range from microseconds to hours, everything from vesicle fusion to muscle contraction to gene regulation.
Rajini Rao Amazing … and isn’t it true that these various uses of calcium evolved independently? (to the best of our knowledge)
Matt Kunzel I think that these mechanisms developed way before and you will be surprised to find that many non-living (outside living body) reactions show similar workings. Then the questions comes if the so-called “living” is just super-organized non-living or what?
I know I am going into some controversial area here but I don’t think there is any evidence that at micro level living show any special physics or chemistry.
Matt Kuenzel , for calcium signaling to evolve, the cell must first develop the ability to (1) sense calcium (2) control calcium levels and (3) respond to calcium. Actually, I’ve never thought of the evolutionary aspects to calcium signaling since it is everywhere. Perhaps the earliest versions simply had to do with moving the ions out of the cell, as was done with sodium and protons. Then, calcium rushing in would have signaled a breach in the cell membrane and perhaps led to cell death. Pure speculation here 🙂 mandar khadilkar , can’t have calcium signaling outside of living cells unless I am misinterpreting your comment.
Rajini Rao I would be over zealous in calling calcium signaling to be existing outside cells. The point was that the apparent complex processes in cells etc are built on very fundamental physics and chemistry rules which are very evident everywhere like polarization of bonds and charges in many biological and non-biological processes.
Yes, very true. Everything in biology is built on chemistry which in turn..takes origins in physics of atoms and bonds.
Looking into the question of when Ca signaling evolved, apparently the Calmodulin gene (a calcium-binding messenger protein expressed in all eukaryotic cells) existed before the eukaryotes diverged and Ca signaling must have come before that. It’s interesting in how many ways that this mechanism has been adapted to so many functions.
Rajini Rao
Little more funny, and cute,and … cheerful then Maxwell with his hammer … ( :
Vengaboys – Up & Down
p.s.Can’t say that i’ve understood article, but i’ve done my best…
nice pic………
very nice
Wowsome
Nature never ceases to amaze me.
Arnav Kalra , I love this mechanism too. Look fast the spring contracts! What are eyes catch is really the slow return to extended state.
It’s really fast. The speed shocks you when you first look at it. How is helical winding so fast?