Abstract: To provide a pectin lyase and a gene for a pectin lyase which can be used in an enzyme preparation for processing plant tissue, and which possesses sufficient maceration activity even under highly acidic conditions. Isolation and purification of a pectin lyase and a gene for a pectin lyase having a molecular weight of 39,500 produced by an Aspergillus filamentous fungus, and possessing a maceration activity and a pectin lyase activity. The pectin lyase has a specified amino acid sequence, an optimal pH of 3.5 for maceration activity, an optimal pH of 4.5 for pectin lyase activity, and deactivates with boiling treatment for 15 minutes at 121° C. Sterilizing heat treatment are unnecessary, because the present invention possesses sufficient maceration activity at pH 3.0-4.0, and the resulting pectin lysate possesses a bactericidal activity and a potent antibacterial activity.