EXPRESSION OF A PECTIN LYASE GENE IN ESCHERICHIA-COLI FROM PSEUDOMONAS-MARGINALIS-N6301

We constructed deletion mutant clones of a pectin lyase gene, and meas ured their pectin lyase activities in Escherichia coli. Pectin lyase a ctivities were detected only in a recA(+) strain but not in a recA str ain of E. coli. We also cloned and sequenced recA from Pseudomonas mar ginalis N6301. The recA from P. marginalis N6301 can complement recA(- ) to form recA(+) in the phenotype of E. coli. Highly conserved sequen ces of recA are observed among E. coli, P. fluorescens, and P. margina lis. From these results, we presume that recA is required for the expr ession of the pectin lyase gene in P. marginalis N6301.