Polygalacturonase (EC 184.108.40.206) (PG) (pectinase) [1,2] catalyzes the random
hydrolysis of 1,4-α-D-galactosiduronic linkages in pectate and other
galacturonans. In fruit, polygalacturonase plays an important role in cell
wall metabolism during ripening. In plant bacterial pathogens such as Erwinia
carotovora or Pseudomonas solanacearum and fungal pathogens such as
Aspergillus niger, polygalacturonase is involved in maceration and soft-rotting of plant tissue.
Exo-poly-α-D-galacturonosidase (EC 220.127.116.11) (exoPG)  hydrolyzes peptic
acid from the non-reducing end, releasing digalacturonate.
Prokaryotic, eukaryotic PG and exoPG share a few regions of sequence
similarity. We selected the best conserved of these regions, which is centered
on a conserved histidine most probably involved in the catalytic mechanism
These proteins belong to family 28 in the classification of glycosyl
May 2004 / Text revised.
PROSITE method (with tools and information) covered by this documentation:
Ruttowski E., Labitzke R., Khanh N.Q., Loeffler F., Gottschalk M., Jany K.-D.
Biochim. Biophys. Acta 1087:104-106(1990).
Huang J.H., Schell M.A.
DNA sequence analysis of pglA and mechanism of export of its polygalacturonase product from Pseudomonas solanacearum.
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