Related Experiment Video
Updated: Jun 2, 2026
08:07
A Micropatterning Assay for Measuring Cell Chirality
Published on: March 11, 2022
On the evolution of homochirality.
1Division of Epidemiology, The New York State Psychiatric Institute, NY 10032, USA. rodrick.wallace@gmail.com
Comptes Rendus Biologies
|April 26, 2011
Summary
Biological homochirality may have arisen from a thermodynamic process favoring the simplest configurations. Earth's low energy density likely
Area of Science:
- Biochemistry
- Thermodynamics
- Astrobiology
Background:
- The origin of biological homochirality (the preference for one mirror-image form of molecules) remains a key question in science.
- Existing theories often lack a robust thermodynamic framework to explain the selection of a single chiral form.
Purpose of the Study:
- To re-examine the origin of biological homochirality using a thermodynamic approach.
- To explore how varying metabolic free energy densities might influence chiral outcomes on Earth and elsewhere.
Main Methods:
- Application of the groupoid approach to stereochemistry within a generalized thermodynamic framework.
- Modeling spontaneous symmetry breaking analogous to Landau's theory.
- Consideration of Darwinian competition between different chiral configurations.
Main Results:
- Limited metabolic free energy on Earth may have favored simpler homochiral states, akin to a low-temperature "freeze-out."
- Subsequent evolutionary processes locked in this initial homochiral condition.
- Higher free energy densities elsewhere could lead to more diverse chiral outcomes, including mixed chirality.
Conclusions:
- The thermodynamic groupoid approach provides a novel perspective on homochirality's origin.
- Earth's homochirality is likely a path-dependent outcome of limited energy.
- Astrobiological implications suggest a broader spectrum of chiral possibilities beyond a simple racemic average.
Related Concept Videos
02:30Chirality in Nature
Chirality is the most intriguing yet essential facet of nature, governing life’s biochemical processes and precision. It can be observed from a snail shell pattern in a macroscopic world to an amino acid, the minutest building block of life. Most of the snails around the world have right-coiled shells because of the intrinsic chirality in their genes. All the amino acids present in the human body exist in an enantiomerically pure state, except for glycine - the sole achiral amino acid. The...
02:05Prochirality
The concept of prochirality leads to the nomenclature of the individual faces of a molecule and plays a crucial role in the enantioselective reaction. It is a concept where two or more achiral molecules react to produce chiral products. A typical process is the reaction of an achiral ketone to generate a chiral alcohol. Here, the achiral reactant reacts with an achiral reducing agent, sodium borohydride, to generate an equimolar mixture of the chiral enantiomers of the product. For example, an...
02:25Chirality
Chirality is a term that describes the lack of mirror symmetry in an object. In other words, chiral objects cannot be superposed on their mirror images. For example, our feet are chiral, as the mirror image of the left foot, the right foot, cannot be superposed on the left foot.
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
02:25Molecules with Multiple Chiral Centers
Molecules that possess multiple chiral centers can afford a large number of stereoisomers. For instance, while some molecules like 2-butanol have one chiral center, defined as a tetrahedral carbon atom with four different substituents attached, several molecules like butane-2,3-diol have multiple chiral centers. A simple formula to predict the number of stereoisomers possible for a molecule with n chiral centers is 2n. However, there can be a lower number where some of the stereoisomers are...
00:58¹H NMR Chemical Shift Equivalence: Enantiotopic and Diastereotopic Protons
Replacing each alpha-hydrogen in chloroethane by bromine (or a different functional group) yields a pair of enantiomers. Such protons are called prochiral or enantiotopic and are related by a mirror plane. Enantiotopic protons are chemically equivalent in an achiral environment. Because most proton NMR spectra are recorded using achiral solvents, enantiotopic hydrogens yield a single signal.
In chiral compounds such as 2-butanol, replacing the methylene hydrogens at C3 produces a pair of...
In chiral compounds such as 2-butanol, replacing the methylene hydrogens at C3 produces a pair of...
01:33Radical Halogenation: Stereochemistry
Stereochemistry is the study of the different spatial arrangements of atoms in a given molecule. The stereochemistry of radical halogenations can be understood from three different situations:
Halogenation to form a new chiral center:
Halogenation to form a new chiral center: