Related Experiment Video
Updated: Jul 19, 2026
09:27
Rapid One-step Enzymatic Synthesis and All-aqueous Purification of Trehalose Analogues
Published on: February 17, 2017
Cryoprotection with L- and meso-trehalose: stereochemical implications.
Seung-Kee Seo1, Michael L McClintock, Alexander Wei
1Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN 47907-2084, USA.
Chembiochem : a European Journal of Chemical Biology
|October 28, 2006
Summary
Unnatural stereoisomers of alpha,alpha-trehalose were tested as cryoprotectants. L- and D-trehalose showed equal efficacy, while meso-trehalose was less effective, indicating stereochemistry impacts cryoprotection.
Area of Science:
- Biochemistry
- Biophysics
- Carbohydrate Chemistry
Background:
- Alpha,alpha-trehalose is a disaccharide known for its cryoprotective properties.
- Understanding the role of stereochemistry in trehalose's function is crucial for developing improved cryoprotective agents.
Purpose of the Study:
- To investigate the impact of stereochemistry on the physicochemical properties and cryoprotective efficacy of alpha,alpha-trehalose.
- To compare the cryoprotection abilities of D-trehalose, L-trehalose, and meso-trehalose using yeast cell cultures.
Main Methods:
- Synthesis of unnatural stereoisomers of alpha,alpha-trehalose (L- and meso-trehalose).
- Cryopreservation of yeast cell cultures in 10% solutions of D-, L-, and meso-trehalose.
- Evaluation of cell viability using the MTT assay.
- Differential scanning calorimetry (DSC) to determine glass transition temperatures (Tg).
Main Results:
- D- and L-trehalose demonstrated comparable cryoprotective efficacy, maintaining high yeast cell survival rates.
- Meso-trehalose exhibited inferior cryoprotection compared to its stereoisomers.
- DSC revealed a significant difference in Tg (nearly 75°C) between D- and meso-trehalose, linked to conformational variations.
Conclusions:
- The biostabilizing properties of alpha,alpha-trehalose are dependent on relative stereochemical factors.
- Absolute stereochemical configuration does not influence the cryoprotective efficacy of alpha,alpha-trehalose.
- Stereochemistry plays a critical role in the conformational behavior and cryoprotective function of trehalose.
Related Concept Videos
01:12Stereochemical Effects of Enolization
The chiral α-carbon of the carbonyl compound is the stereocenter of the molecule. As shown in the figure below, when such a carbonyl compound undergoes racemization under an acidic or basic condition, an achiral enol is formed.
01:28Cryo-electron Microscopy
Conventional electron microscopy (EM) involves dehydration, fixation, and staining of biological samples, which distorts the native state of biological molecules and results in several artifacts. Also, the high-energy electron beam damages the sample and makes it difficult to obtain high-resolution images. These issues can be addressed using cryo-EM, which uses frozen samples and gentler electron beams. The technique was developed by Jacques Dubochet, Joachim Frank, and Richard Henderson, for...
01:17Thermal Electrocyclic Reactions: Stereochemistry
The stereochemistry of electrocyclic reactions is strongly influenced by the orbital symmetry of the polyene HOMO. Under thermal conditions, the reaction proceeds via the ground-state HOMO.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
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...
01:14Keto–Enol Tautomerism: Mechanism
The keto and enol forms are known as tautomers and they constantly interconvert (or tautomerize) between the two forms under acid or base catalyzed conditions. Both the reactions involve the same steps—protonation and deprotonation— although in the reverse order.
01:24Acetals and Thioacetals as Protecting Groups for Aldehydes and Ketones
Acetals are formed by reacting two equivalents of alcohol with carbonyl compounds like aldehydes or ketones. Acetals are unaffected by bases, nucleophiles, oxidizing agents, and reducing agents. They serve as protecting groups for aldehydes and ketones. Acetals can be easily formed and also easily removed via mild acid hydrolysis.
In the presence of multiple functional groups, when selective reduction of one group over the other is desired, groups like aldehydes and ketones that form acetals...
In the presence of multiple functional groups, when selective reduction of one group over the other is desired, groups like aldehydes and ketones that form acetals...