InterPro domain: IPR045032

Pectate lyase 4.2.2.2 is an enzyme involved in the maceration and soft rotting of plant tissue. Pectate lyase is responsible for the eliminative cleavage of pectate, yielding oligosaccharides with 4-deoxy-alpha-D-mann-4-enuronosyl groups at their non-reducing ends. The protein is maximally expressed late in pollen development. It has been suggested that the pollen expression of pectate lyase genes might relate to a requirement for pectin degradation during pollen tube growth [ 1 ].

The structure and the folding kinetics of one member of this family, pectate lyase C (pelC)1 from Erwinia chrysanthemi has been investigated in some detail [ 2 , 3 ]. PelC contains a parallel beta-helix folding motif. The majority of the regular secondary structure is composed of parallel beta-sheets (about 30%). The individual strands of the sheets are connected by unordered loops of varying length. The backbone is then formed by a large helix composed of beta-sheets. There are two disulphide bonds in pelC and 12 proline residues. One of these prolines, Pro220, is involved in a cis peptide bond. he folding mechanism of pelC involves two slow phases that have been attributed to proline isomerization.

Some of the proteins in this family are allergens [ 4 ].

1. Molecular and genetic characterization of two pollen-expressed genes that have sequence similarity to pectate lyases of the plant pathogen Erwinia. Plant Mol. Biol. 14, 17-28
2. Folding kinetics of the protein pectate lyase C reveal fast-forming intermediates and slow proline isomerization. Biochemistry 41, 4713-23
3. New domain motif: the structure of pectate lyase C, a secreted plant virulence factor. Science 260, 1503-7
4. Pectate lyase pollen allergens: sensitization profiles and cross-reactivity pattern. PLoS ONE 10, e0120038