title: [Study of extracellular structures of Agrobacterium involved in bacterial and plant interactions].
abstract: Agrobacterial cells produced straight microfibrils not only when in contact with wheat seedling roots, but also when in contact with each other. After 2 h of incubation, agrobacterial cells were found to form aggregates, in which the cells were in contact either directly or through thick straight microfibrils (bridges) of an unknown composition. The majority of the microfibrils were susceptible to attack by cellulase, although some of them showed resistance to this enzyme. Like the wild-type flagellated agrobacteria, their bald mutants produced long straight microfibrils. The cells surface structures of agrobacteria were examined by labeling them immunocytochemically with colloidal gold conjugated antibodies against O-specific lipopolysaccharides, Vir proteins, and cellulase. Agrobacterial cells treated with acetosyringone and brought into contact were found to contain subpolar and polar cell surface structures. Antibodies against the VirB2 protein were able to interact with a tuft of thin microfibrils located on one pole of the agrobacterial cell, whose vir genes were induced by acetosyringone, but were unable to interact with the surface structures of the agrobacterial cells aggregated in liquid medium in the absence of wheat seedlings.
authors.affiliation: Institute of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, pr. Entuziastov 13, Saratov, 410015 Russia.
authors.forename: M I
authors.initials: MI
authors.lastname: Chumakov
authors.forename: L A
authors.initials: LA
authors.lastname: Dykman
authors.forename: V A
authors.initials: VA
authors.lastname: Bogatyrev
authors.forename: I V
authors.initials: IV
authors.lastname: Kurbanova
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000502:physiology; D001426:Bacterial Proteins / Q000502:physiology; D010944:Plants / Q000382:microbiology*; D012231:Rhizobium / Q000502:physiology*; D037521:Virulence Factors
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D037521:Virulence Factors