Chemical and Functional Properties of Food Saccharides

© 2004 by CRC Press LLC
TABLE 10.6
Pectin- and Pectic-Acid-Degrading Enzymes
Common Name EC Number Systematic Name Application
Protopectinase — PPase Solubilization of pectin
from protopectin
Pectinesterase EC 3.1.1.11 Polymethylgalacturon Removal of methanol
ate esterase
residues
Pectin acetylesterase Removal of acetic acid
residues
Endopolygalacturonase
(PG)
Exopolygalacturonases
(ExoPG)
EC 3.2.1.15 Poly(1,4-α-Dgalacturonide)
glycanohydrolase
EC 3.2.1.67 EC
3.2.1.82
Poly (1,4-α-Dgalacturonide)
galacturonohydrolas
e, Poly(1,4-α-Dgalactosiduronate
digalacturonohydrol
ase
Pectate lyase EC 4.2.2.2 Poly(1,4-α-Dgalacturonide)
lyase
Pectin lyase EC 4.2.2.10 Poly(methoxy-α-Dgalacturonide)
lyase
Exo-pectin lyase EC 4.2.2.9 Poly(1,4-α-Dgalacturonide)exolyase
RG Acetylesterase
(RGAE)
RG Endohydrolase
(RHG)
RG Rhamnohydrolase
(RG-RH)
RG
Galacturonohydrolase
(RG-GH)
Random hydrolysis of α-
1,4 bonds (adjacent to
demethylated
carboxylate groups) in
“smooth” pectin regions
Hydrolysis of α-1,4
bonds in pectic acids,
from nonreducing ends;
mono- and
digalacturonateproducing,
respectively
Random cleavage of α-
1,4 glycosidic bonds in
pectic acids (via βelimination)
Random cleavage of α-
1,4 glycosidic bonds in
pectin (via βelimination)
Cleavage of α-1,4
glycosidic bonds (via βelimination)
from
nonreducing ends
Deacetylation of rhamnogalacturonan
(RG)
Random hydrolysis of
RG to oligosaccharides
Exohydrolase, releasing
rhamnose molecules
from nonreducing ends
of oligomers produced
by RHG
Exohydrolase, releasing
galacturonic acid from
nonreducing ends of
oligomers produced by
RHG
-- continued