Cloning and Characterization of a Pectate Lyase Gene from Erwinia carotovora EC153. D. Trollinger. Departments of Plant Pathology, University of California, Riverside 92521 U.S.A. S. Berry(2), W. Belser(2), and N. T. Keen(1). Departments of (1)Plant Pathology and (2)Biology and Graduate Group in Genetics, University of California, Riverside 92521 U.S.A. MPMI 2:17-25. Accepted 13 December 1988. Copyright 1989 The American Phytopathological Society.

A pel gene cloned from strain EC153 of Erwinia carotovora encoded a pectate lyase that macerated plant tissue with moderate efficiency. This gene, called pel153, was sequenced and found to possess considerable homology with a pectate lyase gene from Yersinia pseudotuberculosis. The Yersinia protein, however, was truncated at the carboxyl terminal end relative to the Erwinia gene product and had a lower isoelectric point. The Erwinia pel153 gene was overexpressed in cells of Escherichia coli, and 56-k Da protein was observed on sodium dodecyl sulfate-polyacrylamide gels. This compares with a molecular weight of 61 kDa for the mature, secreted protein as determined from sequencing data. Southern blot analysis disclosed the presence of the pel153 gene in three different strains of E. carotovora, but mutation of the gene in strain EC153 did not affect its ability to soft-rot potato tubers.