In enzymology, a glucuronan lyase is an enzyme

Enzyme

Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...

 that catalyzes

Catalysis

Catalysis is the change in rate of a chemical reaction due to the participation of a substance called a catalyst. Unlike other reagents that participate in the chemical reaction, a catalyst is not consumed by the reaction itself. A catalyst may participate in multiple chemical transformations....

 the chemical reaction

Chemical reaction

A chemical reaction is a process that leads to the transformation of one set of chemical substances to another. Chemical reactions can be either spontaneous, requiring no input of energy, or non-spontaneous, typically following the input of some type of energy, such as heat, light or electricity...

 of eliminative cleavage of (1->4)-beta-D-glucuronans. This produces either oligosaccharides with 4-deoxy-beta-D-gluc-4-enuronosyl groups at their non-reducing ends, or, if the substrate is completely degraded, glucuronans produce tetrasaccharides.

This enzyme belongs to the family of lyase

Lyase

In biochemistry, a lyase is an enzyme that catalyzes the breaking of various chemical bonds by means other than hydrolysis and oxidation, often forming a new double bond or a new ring structure...

s, specifically those carbon-oxygen lyases acting on polysaccharides. The systematic name of this enzyme class is (1->4)-beta-D-glucuronan lyase. This enzyme is also called (1,4)-beta-D-glucuronan lyase.