Characteristics of Agrobacterium tumefaciens Auxotrophic Mutant Infectivity

Lippincott, Barbara B. (Northwestern University, Evanston, Ill.), and James A. Lippincott . Characteristics of Agrobacterium tumefaciens auxotrophic mutant infectivity. J. Bacteriol. 92: 937–945. 166.—Mutants of Agrobacterium tumefaciens auxotrophic for adenine, methionine, or asparagine are less infectious than the wild-type strain B6 from which they were derived and show increased infectivity on pinto bean leaves when the specific compounds required for growth of the mutants are added to the infected leaf. Reversion to a prototrophic form of nutrition is accompanied by increased infectivity. Tumors initiated by these auxotrophic mutants are shown to arise only at large wound sites where nutritional conditions may be less restricting. The data indicate that, after inoculation, the bacteria pass through a phase in which host-supplied nutrients are utilized for the production of one or more factors necessary for successful tumor initiation.