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Related to Lyases: Isomerases, Transferases


Any of a class of enzymes that catalyze the cleavage of bonds without hydrolysis or oxidation, often resulting in a new double bond or ring structure, or that catalyze the addition of chemical groups to double bonds.

[Greek lūein, to loosen; see leu- in Indo-European roots + -ase.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Biochemistry) any enzyme that catalyses the separation of two parts of a molecule by the formation of a double bond between them
[C20: from Greek lusis a loosening + -ase]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
Scott et al., "Characterization of secreted sphingosine-1-phosphate lyases required for virulence and intracellular survival of Burkholderia pseudomallei," Molecular Microbiology, vol.
Over 30% of known enzymes are metalloenzymes, covering all major enzyme classes: oxidoreductases, transferases, hydrolases, lyases, isomerases, and ligases.
We applied dbCAN [30] with default parameters and identified a total of 301 CAZyme-coding gene homologs (Appendix S4), which includes 127 glycoside hydrolases (GH), 64 glycosyltransferases (GT), 55 carbohydrate esterases (CE), 30 with auxiliary activities (AA), 19 carbohydrate binding module (CBM), and 6 polysaccharide lyases (PL).
They cover considerations for applying process technologies in laboratory-scale and pilot-scale biocatalysis for chemical synthesis; cytochrome P450 progress in biocatalysis for synthetic organic chemistry; using hydrolases and related enzymes for synthesis; non-redux lyases and transferases for forming bonds of carbon with carbon, oxygen, sulfur, and nitrogen; oxidations; reductions; halogenation and dehalogenation; cascade reactions; and biocatalysis for industrial process development.
Snake venom is a mixture of different enzymes like Oxydoreductase Transferase Hydrolases and Lyases.
The former enzyme deesterifies pectin by the removal of methoxy residues and is called pectin methoxy esterase (PME), while the latter splits the main chain and is further classified as polygalacturonase (PG) and pectin lyases (PL) [17-19].
Increased activity of polyphenol oxidase (PPO), peroxidase (POX), phenylalanine ammonia lyase (PAL), and tyrosine ammonia lyases (TAL) had been reported in plants treated with various biotic and abiotic inducers of resistance [33-35].
Differing from other polysaccharide lyases acting on the polysaccharide backbone, xanthan lyase could cleave the linkage between the terminal mannosyl and the glucuronyl residues on the side chain by a [beta]-elimination reaction, introducing a double bond between C4 and C5 of the uronosyl residue and subsequently might be exploited for further chemical modification [13].
According to the mode of action and preferred substrate, pectinases can be briefly classified into two main groups [39]: de-esterification (pectin methyl esterase) which removes methoxyl groups from pectin, and depolymerization (hydrolyses and lyases) which cleaves the bonds between galacturonic acid units.
He covers chiral discrimination in the active site of oxidoreductases, transferases and chiral discrimination, the influence of chirality on the hydrolysis reactions within the active site of hydrolases, the influence of chirality on the reactions in the active site of lyases, and chiral discrimination in the active site of ligases.