Agrobacterium 2.0: optimizing Agrobacterium tumefaciens to enhance biopharming yields

Agrobacterium-mediated transfection is the most widely-used method for genetically manipulating plants. It is central to industrial-scale production of plant-made antibodies and vaccines, and to fundamental molecular biology research. Few improvements to the Agrobacterium microorganism itself have been reported beyond the initial disarming of its virulence factors in the 1980s. This project aims to improve Agrobacterium for optimal transient and stable plant transformations. In proof-of-principle experiments we will demonstrate:

• CRISPR-mediated knock out of beta-lactamases (conferring sensitivity to ampicillin)
• genomic integration of the levansucrase gene (enabling counter-selection of agrobacteria with sucrose), and a fluorescent reporter protein

We will then knock-out the Agrobacterium gene sghA. We hypothesise that this will increase transfection activity by decreasing the local concentration of plant-derived salicylic acid (an inhibitor of Agrobacterium virulence)1. To test the anticipated improvements, optimized Agrobacterium strains will

Chief Investigators