InterPro domain: IPR011050

Microbial pectin and pectate lyases are virulence factors that degrade the pectic components of the plant cell wall [ 1 ]. When the backbone of pectin is methylated it is known as pectin and is cleaved by pectin lyase, and when it is demethylated it is known as pectate and is cleaved by pectate lyase. Pectin lyase from Aspergillus niger displays a single-stranded, right-handed parallel beta-helix topology ( IPR006626 ), where each coil contains three beta-strands and three turn regions. Several other virulence factors share this beta-helix topology, although they vary in the number of coils, including bacterial pectate lyases, fungal and bacterial galacturonases (such as rhamnogalacturonase and polygalacturonase), chrondroitinase B from Flavobacterium sp., iota-carrageenase from Alteromonas sp., pectin methylesterase (PemA), P22 tailspike protein from Enterobacteria phage P22, and the virulence factor P.69 pertactin from Bordetella pertussis that mediates adhesion to target mammalian cells [ 2 ].

1. Two crystal structures of pectin lyase A from Aspergillus reveal a pH driven conformational change and striking divergence in the substrate-binding clefts of pectin and pectate lyases. Structure 5, 677-89
2. Structure and evolution of parallel beta-helix proteins. J. Struct. Biol. 122, 236-46