Lyases


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Related to Lyases: Isomerases, Transferases
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Lyases

 

the class of enzymes that catalyze the nonhydrolytic splitting of certain groups from their substrates, involving the formation of double bonds. Lyases also catalyze the reverse reaction: the joining of groups by double bonds. Lyases are classified as carbon-carbon lyases (some of these are called synthases), carbon-nitrogen, carbon-oxygen, and so forth. Unlike ligases, lyases bring about synthase reactions without the participation of energy-rich (macroergic) compounds.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Saba, "Sphingosine-1-phosphate lyase in development and disease: sphingolipid metabolism takes flight," Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids, vol.
The dbCAN CAZyme annotation program (http://csbl.bmb.uga.edu/dbCAN/) [30] with default parameters and the Carbohydrate Active Enzymes (CAZy) database v6.0 (http://www.cazy.org) were adopted to perform the functional annotations for carbohydrate-active modules and ligninolytic enzymes, which include glycoside hydrolases (GHs), glycosyltransferases (GTs), polysaccharide lyases (PLs), carbohydrate esterases (CEs), and auxiliary activities (AAs).
(a) Pectin lyase (PL) activity was assayed spectrophotometrically by determining uronide at 235 nm [40].
In view of this, the research was planned to determine the effect of different concentrations of zinc (Zn) on biochemical constituents of clusterbean, such as antioxidative enzymes namely peroxidase, polyphenol oxidase, phenylalanine ammonia lyase, and tyrosine ammonia lyase, which play an important role in disease resistance mechanisms.
Like the xanthan lyases produced by Paenibacillus and Bacillus [14, 15], Microbacterium xanthan lyase was active on the intact xanthan and was not associated with endoglucanase [8].
Pectin lyases are the only known pectinases capable of degrading highly esterified pectins (like those found in fruits) into small molecules via [beta]-elimination mechanism without producing methanol.
International contributors to a dozen chapters review biotransformation from the perspective of a major pharmaceutical company and the basics of molecular biology for nonspecialists, then describe key biocatalysts (e.g., lipases, proteases, sulfatases, hydroxal nitrile lyases) and their applications in the resolution of interesting molecules such as drug metabolites.
Genomic and functional characterization of the oas gene family encoding O-acetylserine (thiol) lyases, enzymes catalyzing the final step in cysteine biosynthesis in Arabidopsis thaliana.
The disaccharide products formed from the HS of the urine of a healthy control and a PXE-affected patient by the action of lyases are shown, as an example, in Fig.
These enzymes are grouped into six classes: hydrolases (including proteases, amylases and lipases that break down the main nutrients - fats, carbohydrates and proteins), isomerases, ligases, lyases, oxidoreductases and transferases.
S1P can be converted back to sphingosine by the S1P phosphatase, or it can be irreversibly degraded by S1P lyase to ethanolamine phosphate and hexadecanal (palmitaldehyde).
Pectinases were broadly classified into polygalacturonase, pectin esterase and pectin lyase. Polygalacturonase (PG) acts on the pectin chain by adding a water molecule to break the linkage between two galacturonan molecules; Pectin lyase (PL) acts on the galacturonan chain by removing a water molecule from the linkage to break it and to release its products; whereas, Pectin esterase esterifies the pectin by removing methoxy esters (3).