Characterization of the Erwinia carotovora pelA gene and its product pectate lyase A.

The pelA gene from Erwinia carotovora strain EC encodes pectate lyase A (PLa). The gene was cloned and sequenced. The PLa was purified from Escherichia coli containing the pelA gene on a recombinant plasmid. The optimum pH for the enzyme reaction is at pH 8.5; the optimum temperature for the enzyme reaction is at 40 degrees C; and the purified PLa alone can macerate potato slices. Nucleotide sequence of pelA and the deduced polypeptide sequence of PLa were compared with the pelB gene of E. carotovora and the deduced amino acid sequence of PLb. The nucleotide sequences are 82% homologous and the amino acid sequences are 88% homologous.