title: Cloning and Characterization of Aerobactin Biosynthesis Genes of the Biological Control Agent Enterobacter cloacae.
abstract: Five strains of Enterobacter cloacae that are biological control agents of Pythium damping-off diseases produced the hydroxamate siderophore aerobactin under iron-limiting conditions. Genes determining aerobactin biosynthesis of the biocontrol strain E. cloacae EcCT-501 were localized to a 12.3-kb region, which conferred aerobactin production to Escherichia coli DH5alpha. The aerobactin biosynthesis genes of E. cloacae hybridized to those of the pColV-K30 plasmid of E. coli, but restriction patterns of the aerobactin regions of pColV-K30 and E. cloacae differed. A derivative strain with a deletion in the aerobactin biosynthesis locus was as effective as strain EcCT-501 in biological control of Pythium damping-off of cucumber. Thus, aerobactin production did not contribute significantly to the biological control activity of EcCT-501 under the conditions of this study.
authors.affiliation: Horticultural Crops Research Laboratory, Agricultural Research Service, United States Department of Agriculture, 3420 N.W. Orchard Avenue, and Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon 97330.
authors.forename: J E
authors.initials: JE
authors.lastname: Loper
authors.forename: C A
authors.initials: CA
authors.lastname: Ishimaru
authors.forename: S R
authors.initials: SR
authors.lastname: Carnegie
authors.forename: A
authors.initials: A
authors.lastname: Vanavichit