Bacteria to the Future
Bacteria used to be considered so boring, they were passed over by scientists eager to look where the action was: eukaryotic cells. That was then. Now, Nature reported,1 the little rods and spheres and spirals have lots of tricks up their sleeves worth investigating. “Long dismissed as featureless, disorganized sacks, bacteria are now revealing a multitude of elegant internal structures.” These include spiral skeletons (“sophisticated internal structures that give them shape, and help them grow and divide”) and actin-like motors that control magnetosomes (iron-containing structures) that give bacteria a sense of direction.
Until recently, bacteria appeared to have featureless interiors, even when viewed through electron microscopes. New techniques, particularly cryo-electron tomography, are disclosing wonders that were previously invisible. The discovery by Jeff Errington in 2001 that bacteria do indeed have a cytoskeleton was “one of those few times in a scientific career when you do an experiment that completely changes your way of thinking.” Errington imaged filaments of tubulin wrapped around the inner wall of the cell like the stripes on a barber pole. One theory is that the scaffolding “tells the cell wall’s enzyme contractors outside the cytoplasm where to lay new bricks” (see 01/16/2003). The filaments and associated proteins are also involved in quality control during cell division, and help organize the magnetosomes into sensory organs.
Eukaryotic cells themselves were assumed by 19th century biologists to be featureless blobs of protoplasm. That view, of course, changed dramatically throughout the second half of the 20th century. History seems to be repeating itself with respect to the tinier cells that comprise the most numerous life forms on earth: “For more than a century, cell biology had been practised on ‘proper’ cells – those of the eukaryotes (a category that includes animals, plants, protists and fungi),” Ewen Callaway wrote. “….Hundreds to thousands of times smaller than their eukaryotic cousins, and seemingly featureless, bacteria were rarely invited to the cell biology party.” These discoveries about “simple” bacteria are helping to change that. “We know very little,” said Dyche Mullins [UC San Francisco]. The discovery of the cytoskeleton proved that “There was a lot of organization in bacterial cells we were just missing.” The field is just now opening up after decades of neglect. “There’s a lot of unexplored biology,” he said – and this article didn’t even touch on the subject of the bacterial flagellum.
1. Ewen Callaway, “Cell biology: Bacteria’s new bones,” Nature 9 January 2008 | Nature 451, 124-126 (2008) | doi:10.1038/451124a. Also published on News@Nature.
Some cognitive dissonance in this article was worth noting. Throughout the text, scientists were admitting how little they know about bacteria – and this is with millions of the little cells right under their noses, in real time, in the present. But then, right in the middle of the article, a just-so story was inserted about a mythical past that would be unobservable even in principle:
As cytoskeletons evolved, they took on new chores and snowballed in complexity. At some stage after eukaryotes branched off from bacteria, the eukaryote cytoskeleton seems to have frozen in time. From yeast through to people, its proteins do many of the same jobs, such as towing sister chromosomes to opposite ends of a dividing cell or making sure the endoplasmic reticulum nestles up against the nucleus. More complex eukaryotes might use actin to flex muscles and keratin to make hair, but those tasks are variations on a theme.
Not so with bacteria, says Mullins. Actins that determine cell shape work differently across the bacterial world, and some rod-shaped bacteria, such as tuberculosis, don’t even have them. Due to their vast numbers and unicellular lifestyle, “bacteria can play around with fundamental mechanisms for doing things in a way that eukaryotes can’t”, he says.
This is how the Darwinians get away with calling evolution a “fact” (see next entry). They simply declare it a fact and treat it as if it were a fact. Those only makes sense if f.a.c.t. stands for Fictional Account Creatively Told. It doesn’t have to actually be a fact in the old-fashioned sense. As long as everyone is trained to think it is a fact, the Darwin Party can remain in power, the trains run on time and there is peace in the streets.
The downside is that people’s minds are enslaved to a myth and science suffers. Did Darwinian assumptions hold back progress in bacterial biology? Arguably so. According to the Darwinian mindset, bacteria were just primitive, featureless blobs, till new techniques revealed what is really going on.
A design-theoretic biology might have motivated a different approach. For an organism to be this small yet maintain all the functions necessary for life, there must be incredible nano-engineering and miniaturization going on inside those cells. Let’s find out. Maybe we can even learn some principles that can help us with our micro-engineering questions. The evolutionary paradigm is revolting. Time for a design revolution.