The theme of chemical chirality, or the "handedness"
of the molecular structure of certain substances,
appears in many works of fiction.
== Books ==
Although little was known about chemical chirality
in the time of Lewis Carroll, his work Through
the Looking-glass contains a prescient reference
to the differing biological activities of
enantiomeric drugs: "Perhaps Looking-glass
milk isn't good to drink," Alice said to her
cat.
A supplemental story to The League of Extraordinary
Gentlemen made reference to this, mentioning
in passing that after her return from the
mirror world, her body was mirror-flipped,
presumably down to the molecular level, as
she was unable to digest food afterwards.
In Arthur C. Clarke's short story "Technical
Error" (also titled "The Reversed Man"), a
technician working on a giant superconducting
generator is accidentally "inverted" into
his mirror image, right down to the coins
in his pocket.
When he is found to be starving despite an
apparently-healthy diet, the culprit is determined
to be the amino acids in his food, which are
natural amino acids and opposite in chirality
to those his body now requires.
Isaac Asimov's short story "Left to Right"
concerns an unknown "change in parity", and
mentions biological incompatibilities due
to chirality as one possible consequence.
In Dorothy L. Sayers's novel The Documents
in the Case, a murder is committed that is
designed to appear as accidental death from
eating poisonous mushrooms containing muscarine.
The case is proved to be murder because the
muscarine found in the deceased's stomach
is racemic and therefore synthetic.
In James Blish's Star Trek novella Spock Must
Die!, Spock's mirror-duplicate is later discovered
to have stolen chemical reagents from the
medical bay to convert certain amino acids
to opposite-chirality isomers that his metabolism
requires.
In Spider Robinson's Callahan's Place short
story "Mirror/rorriM On the Wall", a mirror
is constructed of thiotimoline which leads
to a parallel but inverted universe.
A character attempts to smuggle food between
the two universes to sell as a diet product,
since the amino acids are reversed and provide
no caloric value.
In Larry Niven's Destiny's Road, the title
planet's indigenous life is based upon right-handed
proteins.
When human colonists arrive from Earth via
a generation ship, extreme measures are taken
to permit the colony's survival.
A peninsula is sterilized with a lander's
fusion drive, creating the titular "road"
out of fused bedrock.
The area is then reseeded with Earth life
to provide the colonists with food.
Though the soil lacks potassium due to other
factors, necessitating supplements that produce
a hydraulic empire common to Niven's fiction,
the colony otherwise prospers.
Native viruses and bacteria cannot infect
colonists, resulting in longer lifespans.
Sealife quickly recovers, and is consumed
by the colonists as a "diet" food, as their
digestive systems cannot metabolize it into
fat.
Marti Steussy's Dreams of Dawn (1988) has
a similar premise, where the locals evolved
based on right-handed amino acids.
The denouement of Poul Anderson's After Doomsday
relies partly on chirality.
The plot of Roger Zelazny's Doorways in the
Sand centers around a device called the Rhennius
Machine, which reverses objects that pass
through it, down to the atomic level.
It is mentioned that an earlier version of
the machine destroyed itself by reversing
matter to antimatter.
Daniel Suarez's novel Change Agent includes
a character "the Mirror man" who is immune
to neurotoxins due to his mirrored chirality.
In Damon Knight's A For Anything, Leroy Platt
uses a matter duplicator to make food; "Eating
the food, too: Why not?
Just put it through twice, make sure you don't
get any reversed peptide chains."
== Computer games ==
In the Trauma Center series of games, doctors
test for a "chiral reaction" in order to determine
whether or not a patient is infected with
"Gangliated Utrophin Immuno Latency Toxin,"
a fictional, parasitic pathogen more commonly
referred to as GUILT.
A positive reaction means the patient is infected,
while a negative reaction means the patient
has either been cured or is not infected.
In the video game Mass Effect, the turian
and quarian alien species have biology based
upon right-handed amino acids.
Because of this, foods from other species
which have life forms based upon left-handed
amino acids have no nutritional value and
may cause fatal allergic reactions.
The process works both ways—species based
on left-handed acids, such as humans, cannot
consume food from the turian or quarian homeworlds.
Left-handed amino acids are portrayed as being
more common than right-handed versions.
The chirality difference is colloquially referred
to as "Levo" and "Dextro" by characters in
the game.
== Television ==
The television series Breaking Bad features
the "Heisenberg" method of methamphetamine
manufacture, which produces a 99% chirally
pure product.
== See also ==
Chiral life concept, the possibility of making
mirror-image copies of known lifeforms
