|Superclasses:||all carbohydrates → a carbohydrate → a glycan → a polysaccharide → a galacturonan → a modified galacturonan|
Pectin is a structural heteropolysaccharide consisting of a complex set of polysaccharides that is present in most primary cell walls and is particularly abundant in the non-woody parts of terrestrial plants. The characteristic structure of pectin is a linear chain of α-(1-4)-linked D-galacturonate that forms the pectin-backbone, a homogalacturonan.
Diferent types of pectin have different substitutions and additions. A common type is rhamnogalacturonan I, where some D-galacturonate units are replaced by (1-2)-linked L-rhamnose, to which side chains of various neutral sugars branch off, mostly D-galactose, L-arabinose and α-D-xylopyranose.
In nature, around 80% of the carboxyl groups of the galacturonate units are esterified with methanol. Some plants, including sugar beet, potatoes and pears, contain pectins with acetylated galacturonate in addition to methyl esters.
The salt of partially esterified pectins is called a pectinate, and if the degree of esterification is below 5%, a pectate.
Child Classes: methylesterified 1,4-α-D-galacturonosyl (0)
Reactions known to consume the compound:
Not in pathways:
a polysaccharide + H2O → an oligosaccharide
Reactions known to produce the compound:
In Reactions of unknown directionality:
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