Investigating the role of chemotaxis operon genes in agrobacterium tumefaciens

A 1.7 Kb chromosomal DNA of A. tumefaciens C58C1 downstream of chemotaxis operon was sequenced completely in both directions. The comparison of this sequence with sequence databases revealed one open reading frame with strong sequence identity to MCP gene in other bacteria. The sequencing of chromosomal DNA of A. tumefaciens C58 confirmed that this open reading frame has similarity with cytoplasmic domain of McpA. Four mutants of A. tumefaciens C58C1 (Cl/delYl, Cl/delY2, Cl/delB and Cl/delR) were created by in-frame deletion mutagenesis in cheYl, cheY2, cheB and cheR using pKlSmobsacB. Some phenotypic properties of mutants were studied. The cheY2, cheR and cheB mutants showed impaired chemotactic capabilities in both swarming and chemotaxis assays. Deletion of cheY1 appeared to have no significant effect on chemotaxis, under the conditions studied.