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Friday, 19 May 2017

Why enzymes are undeniably designed.

Don’t Be Intimidated by Keith Fox on Intelligent Design
Douglas Axe | @DougAxe


Darwin believed that once simple bacteria appeared on Earth (however that happened), natural selection took over from there — creating every living thing from that humble beginning. And this continues to be the official view of the science establishment to this day.

Being skeptical of that view, my colleagues and I have spent twenty-some years putting Darwin’s idea to one test after another in the lab. As described in a stack of peer-reviewed technical papers, it has failed every one of these tests. I’m convinced, however, that you don’t need a PhD to see why it had to fail. That’s why I based my recent book — Undeniable: Undeniable: How Biology Confirms Our Intuition That Life Is Designed — on commonsense reasoning instead of technical argument.

Biochemist Keith Fox at the University of Southampton didn’t like the book, so he wrote a short critique claiming I got it all wrong. The things I’ve studied for all these years are called enzymes — sophisticated catalysts that handle all the chemical processes inside cells. Based on my work and the work of many others, I claim that these remarkable little factories can’t have come about by any ordinary physical process. I say they’re molecular masterpieces — works of genius. Fox disagrees, and while he doesn’t seem to have done any work in the field, his critique of Undeniable includes his own rough-and-ready theory of enzyme origins.

As I recently recounted, Fox thinks working enzymes started out much smaller than they are today, growing to their present size through the refining work of natural selection. Years ago, I explained in technical detail why this can’t be true — why enzymes must be full-sized and exquisitely shaped to do their jobs. But, again, a major theme of my book is that you don’t have to take my word for this. You can see for yourself that life is designed all the way down to the molecular level.

Here’s one visual example to make the point.




That green thing is a large molecule called tRNA, and the little yellow things are amino acids. For life to work, these amino acids, which come in 20 different kinds, must be connected in special sequences to make chain-like molecules called proteins (enzymes being one class of proteins). If these long molecules were nothing but floppy chains, they would be useless. Instead, their special sequences cause them to fold up into distinct and highly useful shapes, each as well suited to its specific function as any human-made machine.

The crucial instructions for the sequences that cause these machine-like shapes to form are preserved in the form of genes, used in every living cell and carefully passed to successive generations. A set of tRNA molecules like that green one is crucial for reading these genes to make proteins. The tRNA molecules work like clever adapters: their underside recognizes (by perfect fit) a specific short piece of genetic sequence — a genetic word, if you will — while their top part holds the amino acid that, in the language of genes, is referred to by that word.

In order for this to work, something has to make sure each different green thing gets the right amino acid attached at the top — meaning the one corresponding to the genetic “word” recognized down below. As if that weren’t challenging enough, those little yellow amino acids are attached to the green things only with difficulty. They must be forced into position and then locked in place with a chemical bond.

Life’s ingenious solution to these compound challenges is a set of enzymes like the one shown here in blue.



Each of these enzymes recognizes its own type of tRNA molecule, checking the bottom part to make sure it will read the right genetic word and simultaneously recognizing the amino acid corresponding to this genetic word. In power-tool fashion, these enzymes “burn” ATP to forcibly attach the correct amino acid into position on the tRNA (in the above picture you can see the red ATP in place, ready for the correct amino acid to enter the opening and be forced into place).

Sophisticated power tools don’t appear out of thin air, though. So, wanting to think otherwise, Keith Fox imagined much simpler things that could come out of thin air, proposing that these can do crudely what today’s enzymes do so elegantly. Specifically, the little blue blob below is what Fox imagined.



Now, imagination can be useful in science, but only by connecting in a compelling way to reality. As anyone can plainly see, that isn’t the case here. In fact, the absence of evidence to back Fox’s claim up, while significant, isn’t nearly as significant as the fact that we can all see why his claim simply can’t work. Little blobs like that (nothing but two amino acids joined together) can’t possibly verify the bottom of the tRNA…much less do so while recognizing the corresponding amino acid…much less hold the needed ATP in position to power the attachment of that amino acid. And while the comical inadequacy of the size of that little blob is what jumps out at us, this isn’t just about size. Rather, it’s about the necessity of matching shape to function.

Other examples could be given by the thousands (literally) — each showing how woefully inadequate Fox’s little blobs are. But you get the point.

The only thing Keith Fox’s theory of enzyme origins has going for it is that it came from Keith Fox — a fully credentialed and highly competent biochemist at a major research university. In other words, his claim borrows any status it has from his professional standing. But when a scientist, however accomplished, stubbornly wants to see things one way, this borrowed status just isn’t enough.

Surprised? On the one hand, you shouldn’t be…but on the other, you’re in good company if you are. Many people are so persuaded by the stereotypical view of scientists that they can’t imagine how these supposedly uber-rational thinkers could allow their desires to interfere with their reasoning.


Rest assured that they can. Scientist are, after all, just as human as everyone else.

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