February 14, 2019 | David F. Coppedge

Molecular Machine Paper Ignores Evolution

Another paper shows that evolutionary storytelling is neither necessary or useful when investigating molecular machines.

Over the last 20 years, CEH has brought updates about the marvelous rotary motor ATP synthase. This spinning machine shouts “design” to anyone who looks at it and learns how it works. All life depends on these rapidly-rotating engines that continuously synthesize ATP (adenosine tryphosphate), which cells use for energy. The engines are located in the mitochondria of animals, and in the chloroplasts of plants. Spinning at about 6,000 RPM or higher, quadrillions of ATP synthase enzymes are needed to supply energy for life. If they stopped working, you would be dead before you hit the floor.

Few are the scientific papers willing to explain how they originated. Some note differences between species, as if that could account for them. Most authors stay off the question of evolution, preferring to describe new things they are learning, often with exclamations of how “remarkable” and efficient they are. But because “intelligent design” remains a trigger for censorship in academia, few papers use the D-word design either. The reader just has to see it to appreciate it.

ATP synthase dimers are arranged in rows for maximum output.

The ATP synthase engines, we learned, come in pairs called dimers. They are oriented at a specific angle to each other that produces the characteristic folds of the membranes in mitochondria, called cristae. These cristae are important. Previous work showed that these folds funnel the protons produced by upstream molecular machines in the electron transport chain, while vastly increasing the surface area for ATP production.

A new paper in PNAS tells about what is required for dimerization. Blum et al found that “Dimers of mitochondrial ATP synthase induce membrane curvature and self-assemble into rows.” This is good, because cells need orderly rows of the machines to work efficiently. “ATP Synthase Dimers Are Required for Row Formation,” one subsection begins. Mutations in a certain gene, they found, make the mitochondria assemble in a balloon shape with single ATP synthase engines (monomers) scattered at random:

S. cerevisiae mutants lacking ATP synthase subunit g do not form dimers, as subunits g and e are required for dimerization (2, 25). ATP synthase monomers of these mutants are randomly distributed in the membrane (3). Their inner mitochondrial membranes do not develop lamellar cristae but single or multiple balloon-shaped vesicles. ATP synthase dimers are thus a prerequisite for row formation in vitro and for the formation of cristae in vivo.

In other words, mutations damage these vital organelles. Readers will look in vain for any instances of the e-word evolution in this paper. For that matter, no evolutionary terms occur: not natural selection, not phylogeny, not novelty or innovation.

The facts support Michael Behe’s thesis in his new book, Darwin Devolves (see his defense at Evolution News against a hostile review in Science). Destructive mutations can survive “selection” (actually, extinction) he shows, but there are no accounts of improvement due to constructive mutations. Since destructive mutations are far more likely to arise and spread through populations quickly, they will swamp constructive mutations, even if any were to be found. That’s why “Darwin devolves” – the appearance of survival by mutation and “selection” occurs only because mutations blunt or break things. If an organism survives the onslaught of mutational damage, it will be less fit than the unbroken predecessor.


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Comments

  • txpiper says:

    “the appearance of survival by mutation and “selection” occurs only because mutations blunt or break things. If an organism survives the onslaught of mutational damage, it will be less fit than the unbroken predecessor.”

    I have not read Behe’s book, but I believe he uses Polar Bears as an illustration. If that is the case, I think he is wrong. I could agree if all ‘mutations’ were actually random, but the phenomenal adaptations that the white bears acquired should illustrate that they are deliberate alterations.

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