Pectate lyases, cell wall degradation and fruit softening.

This is a brief review of what is known about the role of pectate lyases in plants. The mode of action and three-dimensional structure of microbial pectate lyases is discussed first and then the limited information on the plant proteins is presented. Pectate lyase-like genes have been isolated from a wide range of plant tissues including germinating seeds, pollen, cell cultures, and ripening fruits. The abundance of ESTs for these genes in tomato and the presence of pectate lyase-like transcripts in many other fruits may indicate that these enzymes have a more important role in ripening than previously suspected.