Mirror life

Chiral life concept involves the recreation of regular lifeforms as identical, but mirror-reflected (in the molecular sense), versions of themselves. It is thought that such mirror organisms can be highly incompatible with existing microbes (viruses, bacteria, protozoa, etc.). Hypothetically, it is possible to recreate our entire ecosystem from the bottom-up, in chiral form. In this way, the creation of an Earth ecosystem without microbial diseases might be possible. In some distant future, Chiral Life could be employed to create robust, effective and disease-free ecosystems for use on other planets.

The creation of chiral humans is the basis of 1950 Arthur C. Clarke's story "Technical Error", from The Collected Stories. This story uses a physical accident to transform a person into his mirror image, without providing a scientific explanation. However, modern advances in synthetic biology, like synthesizing viruses since 2002, synthetic bacteria in 2010 or synthetic ribosome in 2013, may lead to the possibility of fully synthesizing a living cell from single molecules, where we could use mirror-image versions (enantiomers) of the molecules building our life in place of the standard ones. Some proteins were already synthesized in mirror-image version, including polymerase in 2016.

Reconstructing regular lifeforms in mirror-image form, using the mirror-image (chiral) reflection of our cellular components could be achieved by replacing left-handed amino acids with right-handed ones, in order to create mirror reflections of all regular proteins. Analogically, we could get reflected sugars, DNA, etc., on which reflected enzymes would work perfectly. Finally we would get a normally functioning mirror reflection of a natural organism - a chiral counterpart organism - with which natural viruses and bacteria couldn’t interact. Electromagnetic force (chemistry) is unchanged under such molecular reflection transformation (P-symmetry). There is a small alteration of weak interactions under reflection, which can produce very small corrections, but these corrections are many orders of magnitude lower than thermal noise - almost certainly too tiny to alter any biochemistry.

Such a chiral lifeform would obviously need to be fed with reflected food, produced by reflected plants. The great advantage, though, is that such chiral organisms should enjoy a disease-free life, completely immune to all viruses and microbes (which virologists are now beginning to understand underlie a huge number of diseases).

Viruses would be completely incompatible with the reflected cellular structures; and bacteria, protozoa and fungi could not function because they would not be able to find normal sugars inside reflected organisms. The reverse sugars circulating in the chiral organism's body would be indigestible as far as normal bacteria are concerned, so any bacterium entering a chiral organism would simply starve to death. The chiral environment is hostile for normal viruses, protozoa, bacteria, etc.

There are also dangers related with this hypothetical possibility. For example, chiral-mirror version of cyanobacteria, which can photosynthesize, could dominate our ecosystem due to lack of natural enemies, disturbing the bottom of our food chains by producing mirror versions of the required sugars.

Direct applications

Direct application of mirror-chiral organisms can be mass production of enantiomers (mirror-image) of molecules produced by our life.

• Enantiopure drugs - some pharmaceuticals have known different activity depending on enantiomeric form,

• Aptamers: "That makes mirror-image biochemistry a potentially lucrative business. One company that hopes so is Noxxon Pharma in Berlin. It uses laborious chemical synthesis to make mirror-image forms of short strands of DNA or RNA called aptamers, which bind to therapeutic targets such as proteins in the body to block their activity. The firm has several mirror-aptamer candidates in human trials for diseases including cancer; the idea is that their efficacy might be improved because they aren’t degraded by the body’s enzymes. A process to replicate mirror-image DNA could offer a much easier route to making the aptamers, says Sven Klussmann, Noxxon Pharma’s chief scientific officer.",

• L-glucose, enantiomer of standard glucose, for which tests showed that it tastes likes standard sugar, not being metabolized the same way. However, it was never marketed due to excessive manufacturing costs.