January 3, 2007 | David F. Coppedge

This Bacterium Moves Like a Tank

Mark McBride (U of Wisconsin) has been trying for a decade to figure out how a gliding bacterium glides.  His conclusion: the microbe has tire treads like a conveyor belt that make it roll over a variety of surfaces, like an all-terrain vehicle.
    According to a U of Wisconsin press release, the Department of Energy (DOE) is interested in this bacterium, Cytophaga hutchinsonii, because it can digest paper and other forest by-products.  This is the first step in converting biomaterial into ethanol, to use as fuel.
    Of the cell’s “parts list,” McBride identified 24 genes involved in its gliding motility.  He attached tiny latex spheres to the cell surface and then watched them move in all directions.  “The cell wall appears to have a series of moving conveyer belts,” he said.  He described these nearly invisible filaments as like tire treads, “designed to help the organism move over a variety of surfaces, like an all-terrain vehicle.”  He believes these structures also convey cellulose into the interior of the cell, toward specialized organelles that digest it.
    Figuring out how this cell digests cellulose is still a work in progress.  Unlike other bacteria that know the trick, this one “may use either a novel strategy or novel enzymes.”  The Department of Energy is interested in this research.  It may help our energy-hungry civilization “find other renewable materials that will be cost-effective alternatives, such as paper pulp, sawdust, straw and grain hulls.”
    What really intrigues McBride about his research on C. hutchinsonii, though, is what makes it go.  He and his students have been comparing it with another gliding bug, Flavobacterium johnsoniae, that although “not closely related,” may “use the same basic machinery to move.”  How different are these two?  McBride claimed, “You are more closely related to a fruit fly than these two organisms are to each other.”

Question: how much did evolutionary theory contribute to this decade-long science project?  Apparently, none.  The press release said nothing about evolution, but quoted the professor using a forbidden word to describe the structures he found: “They are designed to help the organism move over a variety of surfaces, like an all-terrain vehicle.”  Have you ever seen an ATV that emerged by evolution?  How about two that arrived at the same engineering solution independently, with nothing but mutations for information input?
    A mousetrap only takes 5 parts to be considered irreducibly complex; here is one system in one cell that requires 24 parts.  When any one of them was missing, the bacterium was stuck at a standstill.  From one of his comments, McBride apparently believes in evolution, but his research method assumes intelligent design and proceeds without Charlie’s superfluous counsel.  As a benefit of this team’s persistent efforts for more than ten years to understand how these microscopic ATVs work, we may some day be able to fill our car gas tanks with the output of microbial tanks.
    Could we see the world at the bacterial level, we would be astonished at the engineering.  Animators could have fun depicting these microscopic tanks appearing over the horizon, consuming all the cellulose in their path.  What kind of sound track would go with such a scene?  Imagine the crescendo to a climax when each machine divides into two working copies.  Let’s see military engineers try to duplicate that feat with just wood chips for fuel.

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