Agrobacterium-mediated transformation is a commonly used method for plant genetic engineering. However, the limitations of Agrobacterium host-plant interactions and the complexity of plant tissue culture often make the production of transgenic plants difficult. Transformation efficiency in many legume species, including soybean and the common bean, has been reported to be quite low. To improve ...

Agrobacterium tumefaciens uses a type IV secretion system (T4SS) to transfer T-DNA and virulence proteins to plants. The T4SS is composed of two major structural components: the T-pilus and a membrane-associated complex that is responsible for translocating substrates across both bacterial membranes. VirB2 protein is the major component of the T-pilus. We used the C-terminal-processed portion o...

Genetic modification of plant cells by Agrobacterium is the only known natural example of DNA transport between kingdoms. While the bacterial factors involved in Agrobacterium infection have been relatively well characterized, studies of their host cellular partners are just beginning. Here, we describe the plant cell factors that might participate in Agrobacterium-mediated genetic transformati...

The genetic transformation of plants mediated by Agrobacterium tumefaciens represents an essential tool for both fundamental and applied research in plant biology. For a successful infection, culminating in the integration of its transferred DNA (T-DNA) into the host genome, Agrobacterium relies on multiple interactions with host-plant factors. Extensive studies have unraveled many of such inte...

Agrobacterium tumefaciens is a soil phytopathogen that elicits neoplastic growths on the host plant species. In nature, however, Agrobacterium also may encounter organisms belonging to other kingdoms such as insects and animals that feed on the infected plants. Can Agrobacterium, then, also infect animal cells? Here, we report that Agrobacterium attaches to and genetically transforms several ty...

A combination of the crown gall biocontrol strain K-84 and another antagonist JH-l was better than K-84 alone in controlling some Agrobacterium strains. Strain K-84 surprisingly controlled some resistant Agrobacterium strains when heavy concentrations of K-84 were used. Strain K-84 could control sensitive strains of Agrobacterium up to 48 hr. after wounds were inoculated with the pathogen at te...

We investigated the effects of salicylic acid (SA) and systemic acquired resistance (SAR) on crown gall disease caused by Agrobacterium tumefaciens. Nicotiana benthamiana plants treated with SA showed decreased susceptibility to Agrobacterium infection. Exogenous application of SA to Agrobacterium cultures decreased its growth, virulence, and attachment to plant cells. Using Agrobacterium whole...

Exudates of dicotyledonous plants contain specific phenolic signal molecules, such as acetosyringone, which serve as potent inducers for the expression of the virulence (vir) regulon of the phytopathogen Agrobacterium tumefaciens. This induction activates the Agrobacterium T-DNA transfer process to initiate the genetic transformation of target plant cells. Wounded and metabolically active plant...

Agrobacterium tumefaciens has a unique ability to transfer genes into plant genomes. This ability has been utilized for plant genetic engineering. However, the efficiency is not sufficient for all plant species. Several studies have shown that ethylene decreased the Agrobacterium-mediated transformation frequency. Thus, A. tumefaciens with an ability to suppress ethylene evolution would increas...

Agrobacterium is a phytopathogenic bacterium that induces crown gall disease in many plant species by transferring and integrating a segment of its own DNA (T-DNA) into its host genome. Whereas Agrobacterium usually does not trigger an extensive defense response in its host plants, it induces the expression of several defense-related genes and activates plant stress reactions. In the complex in...