ENST: Heterochirality Kills
Researchers found out what
happens if they force a protein
out of its homochiral norm
All proteins in living cells are homochiral: that is, all their amino acid building blocks have the same hand. Amino acids can be left-handed or right-handed, according to an agreed on handedness naming convention. This arrangement is profoundly improbable from an evolutionary standpoint, wrote James F. Coppedge in his book Evolution: Possible or Impossible? (1973, 2002; read chapters 3 and 4 here). Since Pasteur‘s day, scientists have been very familiar with the fact of homochirality in living things, but no one had tested what happens when they force a gene to manufacture right-handed amino acids. The results were not pretty. I wrote about this in the article linked below.
Same-Handed Molecules Are an “Overarching Design Principle” in Life, Say Researchers
by David Coppedge
Evolution News & Science Today, 29 Nov 2022
Homochirality, the same-handedness of building blocks of DNA and proteins, poses a severe challenge for those who deny the intelligent design of life. Design advocates have explained the problem: James Tour, Casey Luskin, Rob Stadler, and many others (see a description of the problem here). The odds of random, blind forces selecting every amino acid in a protein to be left-handed, and every sugar in a DNA chain to be right-handed, are vanishingly small.
Materialists also recognize this hurdle in their origin-of-life theories, because homochirality would have had to become established before natural selection could be called upon for assistance. But what happens when heterochiral molecules do make it into our cells? Bad things happen.
Heterochirality Syndrome
Normally, cells do a good job of keeping our molecules 100 percent homochiral. Stray wrong-handed molecules are either destroyed or turned into the correct hand before a protein or nucleic acid goes into service. A research team in France wondered what would happen if they forced certain genes to go rogue, or heterochiral. (Good thing they tried this on fruit flies and not humans.) They published the dire results in Nature Communications (open access). The Abstract of the paper by Banreti et al., “Biological effects of the loss of homochirality in a multicellular organism,” hints at troubles to come….
Click here to continue reading.
Update 23 May 2025: An article by the American Society for Microbiology discusses the puzzle of chirality. The risks of creating “mirror bacteria” (by intelligent design of microbiologists) are discussed. Such organisms might be invisible to our immune systems and cause health hazards against which we would have no protection. The article has no explanation for the origin of homochirality, suggesting it was just a “frozen accident”
While mirror bacteria would look like their naturally chiral brethren, in many ways they’d be completely alien. They could help determine if the tree of life once sprouted branches of opposite chirality. “This is a deep ‘what if’ question,” said Vaughn Cooper, Ph.D., ASM President-Elect and a professor of microbiology and molecular genetics at the University of Pittsburgh. “Does the bias that we have on Earth exist because of some sort of intrinsic benefit to that combination of molecules, or is it just a frozen accident?”
Homochirality does have an intrinsic benefit (i.e., proteins could not work with mixed handedness). But proposing the accidental origin of homochirality is equivalent to suggesting it was a miracle. Evolutionists seem unable to think outside of their materialist mindset: ‘it exists with a benefit, therefore it evolved.’ In the article, Kate Adamala at the University of Minnesota puts her faith in evolution: “It would be difficult to imagine evolution of any effective biological binding if there wasn’t this pre-agreed [upon] system of chirality.” So what kind of intellectual agents agreed together in advance to do it this way in a mindless material world?