Novel Ti Plasmids in Agrobacterium Strains Isolated from Fig Tree and Chrysanthemum Tumors and Their Opinelike Molecules. Valerie Vaudequin- Dransart. Institut des Sciences Vegetales, CNRS, Avenue de laTerrasse, F-91198 Gif-sur-Yvette Cedex. Annik Petit(1), Christine Poncet(2), Cecile Ponsonnet(3), Xavier Nesme(3), Jeffrey B. Jones(4), Hacene Bouzar(4), W. Scott Chilton(5), and Yves Dessaux(1). (1) Institut des Sciences Vegetales, CNRS, Avenue de laTerrasse, F-91198 Gif-sur-Yvette Cedex; (2) Station de Pathologie Vegetale, INRA, Villa Thuret, F-06606 Antibes Cedex; (3)Laboratoire de Biologie des Sols, Uni-versite Claude Bernard, Blvd. du 11 Novembre, F-69622 Villeurbanne Cedex, France; (4)Gulf Coast Research and Education Center, University of Florida, 5007 60th St. E., Bradenton, FL 34203; and (5) Department of Botany, North Carolina State University, Raleigh, NC 27695 U.S.A. MPMI 8:311-321. Accepted 16 December 1994. Copyright 1995 The American Phytopathological Society.

Galls naturally induced on Fig and chrysanthemum plants by strains of Agrobacterium contained, in addition to other well-characterized opines such as nopaline, three tumor-specific opinelike molecules. These molecules were identified as deoxy-fructosyl-glutamine (dfg), deoxy-fructosyl-5-oxo-proline (dfop), and chrysopine (Chilton et al.., unpublished). Strains isolated from Fig tree and chrysanthemum tumors harbored different and unrelated Ti plasmids as judged by hybridization with various vir and T-DNA probes. They also exhibited different opine-catabolic properties. The strains isolated from chrysanthemum plants (Chry strains) and Fig trees degraded chrysopine, but only the Chry strains used dfg and dfop. Remarkably, other strains of Agrobacterium catabolized these two molecules: dfg was degraded by most pathogenic and nonpathogenic Agrobacterium strains, and dfop by all Agrobacterium strains degrading the opine agropinic acid. These results have strong ecological and evolutionary inferences which fit previous speculation on the origin of opine-related functions.