My Blog List

Sunday, March 6, 2011

Life on Mixotricha paradoxa

No, this is not a newly discovered planet but a flagellated Trichomonad found in the gut of the termite (Mastotermes darwiniensis). Paradoxa helps digest wood fiber in the gut of the termite. It appears that paradoxa moves by using its flagellum. But a closer inspection shows that the flagellum is perhaps only a steering device and the entire structure moves by the locomotion of hundreds of bacteria on the surface of paradoxa.
 
Thus we can document yet another function for the flagellum.  There are several kinds of bacteria on the surface of paradoxa and some are held in what appears to be specialized brackets on the surface of paradoxa.  Some of these bacteria contain their own flagellum and some of the bacteria are spirochetes.  The spirochetes are thought to provide the locomotion on the surface of paradoxa.  It would seem that a most efficient way for this organism to move would be to communicate with its surface motors when it wants to stop or start or go faster.

And there is good reason to want to move fast because Mixotricha paradoxa is hunted and eaten by other creatures lurking in the shadows.  Maybe this is a good reason to live in a  nice safe place like a termite gut.
Questions:
1 Spirochetes move by rotating.  How can a rotating twisting bacterium promote locomotion of paradoxa and yet stay attached to its host if its entire cell body rotates?
2 If paradoxa communicates with its motor bacteria, what form of communication would this be?

37 comments:

  1. 1. On the surface of the mixotricha paradoxa are bacillus-bacteria that are situated in rows on the membrane of the protozoon. It is to the rear of these bacillus-like bacteria that the spirochetes are anchored to in groups from 1-3

    spirochetes.http://www.springerlink.com/content/yqncj8gdbgfn9n2k/fulltext.pdf

    2.Cell to cell communication in bacteria would have to be done by chemical means. The exchange of chemical signal molecules (autoinducers) are ligands to the other bacterial cells, thus creating a metabolic pathway inside of the other cell. This process in a more broader term is called quorum sensing. These quorum-sensing systems can involve both intra and interspecies communication systems.

    http://www.pnas.org/content/100/suppl.2/14549.full

    ReplyDelete
  2. Not a whole lot is known about the relationship between paradoxa and its symbiotic bacterial motors. One thing that is important for spirochete locomotion is the brackets that hold it in place on the paradoxa. These brackets form a “posterially oriented regular attachment site…which allows the spirochetes to propel the flagellate cells forward. (Cleveland, Grimstone).” This bracket mechanism allows the sprirochetes to move and also stay attached to the host cell.


    http://adsabs.harvard.edu/full/2002ESASP.518..193K

    Chemical communication may be a method that paradoxa uses to communicate with its symbionts. It is possible that the host cell secretes a chemical that stimulates movement from the surrounding bacteria.

    ReplyDelete
  3. Shannon and Gage, Good work. I would still like to see, at least some speuclative model as to how the spirochetes could provide locomotion while remaining attached to the organism. It seems to me that there could be a very fascinating mechanism

    ReplyDelete
  4. Ok, pure speculation: maybe its like the fins of fish..the ones that rotate on the side and propel the fish forward. Those are still attatched to the fish, but yet cause it to move. Maybe its like that, but a seperate organism attatched to the surface of the paradoxa, and as the paradoxa needs to move, it sends some sort of signal to propel the spirochetes and move. Maybe the communication is some sort of cellular signaling. As specific cells in the paradoxa interact with eachother and detect the need for movement, they send send some sort of signal to the paradoxa's surface which the surface of the spirochetes detects. I'm not sure if that's even plausible but...just an idea.

    ReplyDelete
  5. 1. In researching I found that there hasn’t been a lot of research into how the bacteria attach to Mixotricha paradoxa yet still maintain their motility (or maybe I just can’t find it). Therefore I had to speculate as to how these two qualities could be preserved.
    Since spirochetes are gram-negative they have two membranes, an inner and an outer one. Between these two membranes there is an axial filament made up of endoflagella. These flagella rotate around the bacteria causing the spirochete to corkscrew. Therefore the axial filament needs to be free to rotate around the inner membrane. A possible mode that allows attachement to Mixotricha yet free movement is a protein that spans both the spirochete outer membrane and the protozoan membrane. This protein could possibly be some gap-junction-like protein, allowing passage of molecules between the two cells as a form of communication. Because of the fluidity of the phospholipid membrane the spirochete would still be free to move while staying connected to the protozoan.
    Another idea is that spirochete movement is modified when attached to Mixotricha paradoxa. The spirochetes cannot live apart from the protozoan as was made clear by the fact that they can’t be cultivated alone. Therefore we aren’t completely sure how the spirochetes (Treponema spirochete and Canaleparolina darwinienisis) move on their own. They could only have endoflagella on half of their cell and therefore the whole cell isn’t rotated. If this was the case they would act like propellers more than a corkscrew.
    2. As we learned from the video on quorum sensing, interspecies communication is, as the name implies, communication between two different species. The mode of this communication between paradoxa and its bacteria is still an area with a lot left to discover.

    ReplyDelete
  6. 1. This is just an idea but couldn't proteins form into a ball bearing "structure" with the bacteria in the middle, held in place by a negative much like a cell protein in the cell membrane. This would allow the bacteria to move freely but still held in place so that they would be able pull the paradoxa forward
    2. I'm thinking something fast maybe proteins or faster such as with Na and Cl ions in nerve cells. If the cells are so close together couldn't there extracellular proteins and other structures connect with each other?

    ReplyDelete
  7. This comment has been removed by the author.

    ReplyDelete
  8. The structure and functions of the different parts of the Paradoxa is interesting. After reading about this paradoxa, I pictured an iRobot (vacuum) with a flagellum :)

    Due to the Mixotricha paradoxa being hunted and eaten by other creatures, it is reasonable to say that the paradoxa has a flagellum and bacteria (that also contain their own flagellum) on the surface of the paradoxa in order to move fast.

    The bacterium that is attached to the surface of the paradoxa can promote locomotion and yet stay attached to its host because their axial filaments only rotate, and the bacterium is attached to specialized brackets (protrusions of the cell surface). The axial filaments are embedded in the cell wall of the bacteria. Also the rigidity of the filament allows the bacteria to move.

    http://adsabs.harvard.edu/abs/2002ESASP.518..193K

    https://mysite.dmacc.edu/personal/fmkrick/instructor/Microbiology%20with%20Diseases%20by%20Taxonomy%203rd%20ed/ch_03_lecture_outline/spirochetes.html

    ReplyDelete
  9. 1 Spirochetes move by rotating. How can a rotating twisting bacterium promote locomotion of paradoxa and yet stay attached to its host if its entire cell body rotates?
    Mixotricha paradoxa is definitely falls victim to being hunted and eaten by other creatures, they have two membranes one outer and one inner one. there are many possibly theories however i think there has to be something in between the membranes that allows it to spin fast.

    2 If paradoxa communicates with its motor bacteria, what form of communication would this be? This takes place between two different species, For this to happen there must be chemicals involved i am thinking there has to be certain proteins actively working together for this to work.

    ReplyDelete
  10. 1: The rotating twisting bacterium promote locomotion and still stay attached to its hose because it must have some sort of motor that allows the bacterium to still stay attached. This motor must allow it to stay attached while rotating at the same time. This motor acts as a holding device for the twisting bacterium so that won’t be removed from the host.
    2: It seems like the paradoxa communicates with the motor via chemical signaling. This kind of signaling occurs between local and distant cell communication and also communication by direct contact between cells. It could also communicate through a local regulator. A local regulator is a chemical signal that influences only neighboring cells. Having a local regulator would make sense for how the paradoxa would communicate with its motor bacteria because this is all on a very small, cellular level, so cell to cell communication would be probable and seemingly likely.

    ReplyDelete
  11. 1 The spirochete on the Paradoxa probably are connected at one end of the spirochete and the rest of the cell rotates moving the Paradoxa. The specific molecular level of interaction would be difficult to speculate but the spirochete probably has some anchoring device on one end so as to embed itself into the host's membrane which would provide stability and allow the spirochete to continue to rotate moving the host cell.
    2 The Paradoxa would probably use a chemical messenger to communicate to the spirochete as to where it wanted to go. The host would respond to stimulus and send a messenger to it's membrane and it would go out to the spirochete to signal where it should move the host cell.

    ReplyDelete
  12. 1. Spirochetes promote locomotion of paradoxa and yet stay attached to its host by attaching to some sort of "brackets" on the surface of Mixotricha paradoxa. These brackets form a posteriorly oriented regular attachment site for the spirochetes, which allows the spirochettes to propel the flagellate cells foreward.
    Source: http://articles.adsabs.harvard.edu//full/2002ESASP.518..193K/0000193.000.html
    2. The communication between Paradoxa and spirochetes is through the cell signaling process once they sense there are food coming in the way.

    ReplyDelete
  13. 1) I would guess that the Spirochete is attached to the Paradoxa, yet remains spinning, because of the brackets. The brackets could act like an open-ended "carport." The Spirochete are located inside and spin. To avoid escaping out the front or the back of the bracket, the ends of the "carport" would be slightly smaller than the diameter of the tubular Spirochete. It would be trapped, but not actually attached to the Paradoxa. the open ends of the brackets allow for the movement of fluid through the "carport," so that the spinning of the Spirochete propels said fluid through and pushes the Paradoxa forward. Think of putting a ball on a table, and then setting a perforated cup over the ball. The ball can still roll around inside the cup, but it can't escape, and so it stays "attached" to the table even as the surrounding air moves through the cup.

    ReplyDelete
  14. 2) Perhaps to communicate with the motor bacteria, the Paradoxa secretes an ion such as calcium, creating a gradient around the bacteria. When the bacteria takes in the calcium (a stimulator) by diffusion, the resulting calcium buildup inside the bacteria would trigger the bacteria to spin.

    To stop the spin, the Paradoxa could create a gradient with something like potassium, which isn't a stimulator like calcium is. When the bacteria took in the potassium, it would get ride of calcium (maybe absorbed by the cell, and used to stimulate digestion if the bacteria moved the cell toward food...) to maintain proper charge, and the stimulation to spin would stop.

    ReplyDelete
  15. 1. I was thinking that there must be a special type of chemical bond between the bacteria and the paradoxa, but it has to be a weak bond in order to release and attach quickly. Or, the bacteria could be attached on one end of the cell to the paradoxa and the other end would just rotate freely.

    2. I think that the cell would use signaling to set off a chain of reactions to make the bacteria spin, thus helping the cell escape from potential attacks. It would be interesting to see, because the signaling would have to go from the paradoxa to the plentiful bacteria attached to it.

    ReplyDelete
  16. 1. I agree with Kayla Noch suggestions about the location of the Spirochete. There is one particularly that I really agree that explains the theory of how the Spirochete can promote location while still attached to the Paradoxa. It would make sense that sense this bacteria is gram negative that the two membranes with the axial filament made of endoflagella would promote the spirochete to corkscrew. The axial filament would get its full range of motion to rotation to move its host. Do you have any objections or concerns about this theory Dr. Francis?
    2. Quorum sensing would be the mode of communication between the Spirochete and Paradoxa. This relationship is used by bacteria to coordinate actions and behavior. Some social insects even use quorum sensing to communicate about where to meet.

    ReplyDelete
  17. Marcy and Kayla,

    I am not sure I totally understand your theory. But I think you are saying that perhaps the spirochete is attached to paradoxa via its outer cover but this does not prevent the flagellum/axial filament from rotating. That indeed might work. My guess is that it would take a lot of bacteria with filaments moving in unison.

    ReplyDelete
  18. 1)It looks like paradoxa is specifically designed for bacteria based locomotion. It has brackets built into it's membrane that the bacteria attach to so that they can rotate, providing transport, but still stay attached to the cell.
    2) Could the two organisms communicate in the same way that nerves communicate? The "message" would have to pass through a small gap between the bacteria and the protist, just like neural transmitters have to pass through the synaptic cleft?

    ReplyDelete
  19. 1 Spirochetes move by rotating. How can a rotating twisting bacterium promote locomotion of paradoxa and yet stay attached to its host if its entire cell body rotates?
    I think that the moving of the spirochetes do not affect it attachment to the paradoxa, but yet it forms a symbiotic relationship to the paradoxa. The spirochetes have a mutualistic relationship with the paradoxa, and maybe use its energy to rotate and move the cell. Or if you think in mechanical terms, the spirochetes are hooked onto the paradoxa on the inside but its bacterial "hairs" are on the outside of the cell helping to move it.


    2 If paradoxa communicates with its motor bacteria, what form of communication would this be?
    I would think that the way the paradoxa communicates with its motor bacteria is through chemical signaling. The bacteria is connected and forms a symbiotic relationship with the paradoxa, so therefore specific ions are secreted from the paradoxa to the bacteria, signalling it to begin spinning and rotating.

    ReplyDelete
  20. There are so-called 'brackets' on the cell surface that form an arrangment site for the spirochetes. This allows the spirochete to propel the flagellate cells forward. There could also be a motor or type of bond that holds the bacteria in place.

    It is still unknown how the flagellates and the spirochetes communicate and coordinate movement. Chemical communication would be a means of communication in the cell. Cell signaling, or means of a stimulus could provide the means for communication for the cell as well.

    ReplyDelete
  21. 1.Based on speculation, bacteria could be attached to the cell like a ball and socket joint, similar to our shoulders. Our shoulders are clearly attached to our bodies but we are able to rotate them quite freely as well, and in water, they propel us forward. But according to an article I found on the Smithsonian/NASA Astrophysics Data System website, these spirochete are attached to the Paradoxa perpendicularly which still allows for rotation. These bacteria are situated in rows and as each one rotates, the together propel the paradoxa forward. It’s actually an amazing system. The bacteria are attached to brackets that arise from the surface of the cell, the bacteria are not actually touching the cell itself. That is why their rotation is not hindered in any way.

    2. These are separate entities so it would not be the same as a brain messaging to other parts of the body I’m assuming. Maybe there is a signal the paradoxa can send out via its cell surface and the bacteria are able to respond to these signals. I think Sam may be on the right track though. It sounds similar to our nervous system and a very likely possibility. There has to be a stimulant of some sort.

    ReplyDelete
  22. 1. The spirochete bacteria is anchored to the paradoxa by some type of bracket and then the spirochete rotates and pushes the paradoxa along. The spirochete propels the paradoxa in the same way that a screwdriver pushes a screw. The bracket may work by some kind of attachment between the spirochete and the polysaccharide coat on the paradoxa surface.
    2. The paradoxa would have to communicate with the bacteria on its surface by some sort of chemical means. Perhaps the paradoxa releases paracrins which are taken in by the bacteria.

    ReplyDelete
  23. 1. When I first read this, I figured that there must be some kind of way that the spirochete can get a foothold on the paradoxa and attach to hold fast so the spirochete can provide locomotion for the paradoxa.
    "On the paradoxa, there are bumps or appendages where the spirochetes attached, and a bacillus which lodged on the other side of the bump." http://www.inplainsite.org/html/animals_that_prove_creation.html
    2. Because the spirochete is attached to the paradoxa and so there is a connection between the two, I was wondering if maybe the paradoxa could send some sort of signal to let the spirochete know which direction they wanted to move and whether they wanted to stop or go. If that is possible then it could be some chemical signal, or maybe another form. I'm not really sure.

    ReplyDelete
  24. The spirochaete has many polar flagella that are confined within the outer membrane and wind down the cell from one of its end. There is bracket that connect the spirochaete with the membrane, and when it rotates paradoxa will follow along. Paradoxa communitcates with the bacteria by cell signaling. Maybe by exchanging and phospholating molecules or proteins.
    What is spirochaete's benefit from attaching with the paradoxa?

    ReplyDelete
  25. 1. Maybe a ball bearing system could work. All of the bacterium on each side could be spinning in the same direction along the plasma membrane of the paradoxa. They could be spinning in place, moving the bacterium forward. They could be attached by weak bonds (Ionic or Hydrogen) to allow for motion and attraction.

    2. Paradoxa could communicate with the bacterium by exchange of phospholipids via Acytedaltransferase. Certain phospholipids could stimulate certain effects in the bacterium. For example, there could be directional receptors on the plasma membrane that could be transferred to change the direction that the bacterium is spinning.

    ReplyDelete
  26. 1. The spirochaete must be attached at the axis of the spirochaete. This could be done by allowing the end of the spirochaete to contain a ionic charge, and the other end to have the opposite ionic charge. As the charges would keep the spirochaete attached but still able to move. Another possible solution is presented in the spirochaete's structure. The spirochaete contains two membranes, which allow the spirochaete to spin. This means that the outer membrane could simply be attached while still spinning in a spiral motion. This corkscrew action could propel the water or other liquid the paradoxa is travelling in to be pushed away, and thus propelling the paradoxa.
    2. The paradoxa could communicate using either chemical signals. If the spirchaete was held in place using ionic compounds, the paradoxa could change the concetration of the ions and thus change the intensity of the attachment. If the attachment was less, a higher rate of rotation could occur, thus directing the cell in that direction. Again, this is purely speculation.

    ReplyDelete
  27. 1. So what I picture in my brain is a boat with a propellor . The spriochete acts as the propellor while the paradoxa is the boat! There must be a motor... here's a quote from "Molecular Basis of Symbiosis".
    "The rod-shaped bacteria and the spirochetes are attached to regularly arranged protrusions of the cell surface. Interestingly, Cleveland and Grimstone found that the spirochetes propel the cells....For hydro-mechanical reasons, it seems that cilia, flagella, sperm tails and spirochetes should automatically synchronize their movement when undulating in close proximity."

    2. I think everyone else got it right when they said it communicates with the motor by chemical signaling... ;D

    -Sarah Gonzales

    ReplyDelete
  28. 1. It somehow attaches to the cell surface..I would think the way Trent said it, maybe by some kind of charge, maybe not an ionic, but possibly..that seems like the best possible way for the spirochaete to still be attached to the paradoxa.
    2. hm...signals to the bacteria to the mixotricha would have to be possibly through the charges again? ...maybe from the dna or from the protein channels? I'm not quite sure about this one, but I know that God is sovereign and He is the one that sustains things together, and I praise Him for that! :)

    ReplyDelete
  29. my theory would probably be that of a rotor like machine that allows the bacteria to spinning in the same direction and this would allow the bacteria to stay the on the surface of paradoxa by a friction attraction maybe. this attraction is purely hypothetical but it could be ionic.

    2 maybe the the bacteria is communicating by cell signaling but it is using the fluid around it to link ahead to communicate.

    ReplyDelete
  30. It appears to me that the brackets that the bacteria are what hold it in place, probably by some integral proteins similar to the way cells bind to the ECM, I don't know that an ionic charge would be enough to hold it in place. I kind of like where trent is going with the idea that they are able to move because of their double membrane. The signaling, I would guess, is some chemical signaling pathways or possibly signaling from integral proteins that are used to hold them in place, the similar to the way integral cells signal to adhere or release from the ECM.

    ReplyDelete
  31. 1 The paradoxa is a rod shaped bacteriai it is also composed of many spirochetes. The spirochetes bind to the host. This allows its entire body to rotate and still be attached. Even though everything is moving it won’t come off the host due to the binding.
    2 I am not completely sure on the naming of the communication but it would seem to me that the paradoxa would directly communicate with the motor bacteria since its moving so fast and the movements need to be done quickly. This means it would be very hard to have signaling from another organism.

    ReplyDelete
  32. It is said that flagella mobility is “parallel to the cells long axis and individual cells move forward or backward perhaps using a irrotational traveling helical wave” (Bergey's manual of determinative bacteriology Bergey). Pretty much it’s a contraction of waves that move from one end of the flagella to the other producing a forward or reverse motion. So maybe since its moving horizontally, theoretically like an or of a boat, than it will stay attached but just the velocity of this helical wave and its “geometry” will move the lil guy. I believe it would be a chemical signaling.

    ReplyDelete
  33. 1. The rod-like bacteria are attached to the surface of the paradoxa on regularly arranged protrusions by so-called “brackets.” It seems like it would work like an axle, the axle is able to rotate but still remains attached to the paradoxa via the specialized brackets.


    2. If paradoxa communicates with its motor bacteria, what form of communication would this be?
    Paradoxa probably communicate the same way different cells communicate with eachother—chemically. The chemicals exchanged that are used to communicate are called autoinducers. The amount of autoinducers are also directly related to amount of bacteria present, allowing them to synchronize activities better and function as a group more effectively.

    ReplyDelete
  34. 1. Research on this is quite scarce, therefore I'm not entirely sure about this, but by my guess is that the spirochetes are somehow anchored to the host. This is probably how it can stay attached despite entire cell rotation.

    2. Communication between these cells is achieved through chemical signal exchange by signal molecules. These molecules are called autoinducers. Also, this process is called quorum sensing, and through this process, bacteria are allowed to check for the presence of other bacteria in their environment. And when they do, they are to respond accordingly.

    ReplyDelete
  35. 1. The anchoring of the spirochete to the paradoxa may be achieved by the force exerted by the moving spirochete. I think the brackets may prevent the spirochete from moving away from the paradoxa on the sides. However, I think the brackets would not have to be smaller than the spirochete as this may restrict rotation. Instead, if it were minimally larger, just large enough for the spirochete to fit and rotate within as the force generated by rotation would keep the spirochete in close proximity to the paradoxa and thus in the bracket.

    2. The interaction between the paradoxa and spirochete may be characterized by chemical signaling. I think cell-cell interactions requiring contact may be hindered by the force exerted at the point of contact.

    ReplyDelete
  36. 1 Spirochetes move by rotating.  How can a rotating twisting bacterium promote locomotion of paradoxa and yet stay attached to its host if its entire cell body rotates?
    my theory that i have formulated from research and reading the other comments would be that the organism is attached to its host at all time at some point. it is never floating off by itself. that point is just changed throughout the movement of the Spirochetes. as the placement changes and the Spirochete rotates, it moves along the host. this goes to show the complexity of the organism in even just its movement. the socket theory also seems very plausible.
    2 If paradoxa communicates with its motor bacteria, what form of communication would this be?
    the Spirochete attaches itself to the host, and maybe it intercepts the signaling system that the host already has. maybe it is through chemical signaling as each organism emits its own chemical signals, compelling a response from the other organism. is it through the location of the Spirochete on the host? maybe i am totally off on this one, i am not sure, i am trying to brainstorm a little more. is there even a way for the spirochete to even attach to any form of a "nervous" system because it is constantly moving?

    ReplyDelete
  37. There are so-called 'brackets' on the cell surface that form an arrangement site for the spirochetes.

    This allows the spirochete to propel the flagellate cells forward. There could also be a motor or type of bond that holds the bacteria in place.

    It is still unknown how the flagellates and the spirochetes communicate and coordinate movement. Chemical communication would be a means of communication in the cell. C

    ell signaling, or means of a stimulus could provide the means for communication for the cell as well.

    ReplyDelete