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Phytopathogenic Erwinia carotovora subsp. carotovora (Ecc) LY34 causes plant tissue maceration by secretion of pectinolytic enzymes such as pectate lyase (PL) existed as multiple isoenzyme form. Genomic DNA from Ecc LY34 was digested with Sau3AI and ligated into the BamHI site of pBluescript Ⅱ SK^+. Among them, a clone hydrolyzing polypectate was selected and its DNA was digested with BamHI. Through the subsequent subcloning the resulting 3.1 kb fragment, corresponding to a pelCI, was subcloned into pLYPA 100. The structural organization of a pelCI gene encoding a 374 amino acid residues consists of an open reading frame (ORF) of 1,122 by commencing with a ATG start codon and followed by a TAA stop codon. PelCI contained a typical prokaryotic signal peptide of 22-amino acid. Since the deduced amino acid sequences of PelCI protein was very similar to those of PelIII of Erwinia carotovora subsp. carotovora, and to those of Pel3 of Erwinia carotovora subsp. atroseptica, and to those of PelC of Erwinia carotovora subsp. carotovora, it belong to the same family PLbc group. The 374-amino acid PelCI had a calculated Mr of 40,507 and pI of 7.60.
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