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Bacteria Propel Themselves with Slime Jets

Posted by ryuzaki0 on from the ka-WHOOSH dept.

galactic_grub writes "Scientists have discovered that some bacteria propel themselves along using tiny jets of slime. According to this story on NewScientistTech, the researchers previously thought the slime was a lubricant. They believe the same technique could be used to move nano-devices around."

14 of 50 comments (clear)

  1. Eating nanobots? by fbjon · · Score: 3, Interesting
    Is it just me or are there no comments in this story?

    In any case, how would the nanobots produce the propellant fluid, they'd have to be able to consume something? Perhaps they're counting taking in and storing some available fluid while passing through, like in the human blood stream, or somesuch.

    --
    True confidence comes not from realising you are as good as your peers, but that your peers are as bad as you are.
    1. Re:Eating nanobots? by Forbman · · Score: 3, Interesting

      Well, most animal slime is a mix of sugars and water. The sugars hold a large amount of water, relatively speaking, so if it's the same with bacteria, then the bacteria does not have to expel much of the sugar mix, so the metabolic demands are gonna be relatively small.

    2. Re:Eating nanobots? by Anonymous Coward · · Score: 5, Insightful

      You're assuming propellers work the same at nano scale. They don't.

      Remember, this is a realm of counter-intuitive phenomena that you can't just "gut feel" your way around.

      Odds are good that if bacteria do it, then it's an extraordinarily efficient way to do things, and we should seriously consider it. Remember that
      a) they evolve much faster than we do
      b) are much older (predating eukaryotes by 2 billion years or so)
      c) they live at the micro/nano scale boundary.

      Call me when you've got that kind of experience under your belt ;)

    3. Re:Eating nanobots? by Short+Circuit · · Score: 3, Informative

      If I recall correctly, some bacteria, such as salmonella, do use propellors...tiny little screw-like hairs that the bacteria rotate.

      --
      tasks(723) drafts(105) languages(484) examples(29106)
  2. With Apologies To Bill Watterson by American+AC+in+Paris · · Score: 4, Funny

    Apparently, scientific progress goes "Ew."

    --

    Obliteracy: Words with explosions

  3. Nanobots by Eightyford · · Score: 3, Funny

    They believe the same technique could be used to move nano-devices around."

    Would that really be the most efficient way of moving a nano-device? I doubt it. I think we'll see little sperm bots first.

    --
    Religion for nerds. Stuff that really matters
    1. Re:Nanobots by linzeal · · Score: 4, Funny

      I want women to have little anti-sperm nano robot defenses so I can get like mecha-suit sperm bots that tries to invade her womb like little futuristic crusaders to implant my seed. Also they could walk around and under people's doors to impregnante women while they sleep. This is what scientific progress means to me.

      --
      An Education is the Font of All Liberty
  4. Bacteria, too? by jcr · · Score: 4, Funny

    Gee, I thought it was just politicians...

    -jcr

    --
    The only title of honor that a tyrant can grant is "Enemy of the State."
  5. Nick by deanj · · Score: 3, Funny

    I think the implication of this are obvious. Let me be the first to say:

    I, for one, welcome our Nickelodeon overlords.

  6. Funny you should mention that... by Glog · · Score: 3, Funny

    "Self-propelled through slimy jets" is also part of the job credentials of any current and/or future RIAA president. And yes, many many bacteria have suffered and died in order to perfect this method of propulsion.

  7. The DETAILS may be new, the idea isn't! by maubp · · Score: 5, Interesting

    "Scientists have discovered that some bacteria propel themselves along using tiny jets of slime".

    No - that has been known for a long time. This research mearly elucidates the mechanism. Which is nice. But, in addition to the slime nozzles at the back end, .

    Did you know that at the front end Myxo bacteria have "grappling hooks" which that can extend and then retract? Search for pilus retraction...

    Or that they are pack hunters? Or that they will commits suicide to save their buddies?

    Myxobacteria - they're great!

    1. Re:The DETAILS may be new, the idea isn't! by maubp · · Score: 2, Informative

      Link should be this, and I have noticed at least one spelling error in my above post.

      I should really learn which button is "submit" and which is "preview" ;)

    2. Re:The DETAILS may be new, the idea isn't! by Dachannien · · Score: 3, Interesting

      Or that they will commit suicide to save their buddies?

      The amoeba Dictyostelium discoideum will also sacrifice itself to help propagate the species when food supplies are dwindling. Rather than just die and release protective substances, however, the individual cells actually form a multicellular slug capable of locomotion. Once the slug has migrated, it sends up a stalk with a spore-laden "fruiting body". The cells in the stalk die, while the spores are able to travel through the air to an environment where food is hopefully more plentiful.

      Of course, being an amoeba, Dicty can locomote without the need for slime jets.

  8. This may seem inefficient... by san · · Score: 5, Informative

    This may seem a very inefficient way to move about, but things work very differently on the lengthscale of bacteria.

    For example, most moving bacteria use propellor-like objects (flagellae) to propel themselves, but the way they work is very different from propellors.

    Propellors use Bernouilli's principle to create a pressure difference between the front and the rear of the propellor, thereby 'sucking' themselves forward.

    Bacteria, because they're so small, live in a surrounding where water has an effective viscosity higher than molasses on our lengthscale (it has to do with a dimensionless number for friction in hydrodynamics called the Reynold's number, that scales with inverse length).

    Bacteria have to push themselves forward in something that really doesn't want to move and creates a lot of friction; all kinds of movements that we would think of intuitively possible are impossible under these circumstances. For example, some hydrodynamics people talk about the 'scallop theorem', which states that at these conditions it's impossible something to move forward like a scallop: rapidly closing its shell and opening it again.

    Most flagellae are either spiral structures or stiff rods that get swayed back and forth; none use Bernoulli's effect, but tend to make use of the high viscosity by pushing against the fluid.

    These bacteria make a starch gel to propel themselves: the sugar concentration doesn't need to be very high to get a decent gel, and the speeds they obtain sound incredible (usually we're talking 10 microns per minute, not per second).