47 THE MECHANISM INFECTION OF AGROBACTERIUM TUMEFACIENS The Mechanism Infection of Agrobacterium tumefaciens (original) (raw)

Genetic engineering in plants has been aided by the use of Agrobacterium tumefaciens, a Gram negative bacterium that allows the introduction of genetic information into cells. This has revolutionized the field, improving cultivars by expressing traits that would not be possible to obtain by classical methods. As such it is a remarkable system that permits to test in vivo the effect of proteins originated from different species in a particular plant. The wild type Agrobacterium carries two types of genes for transformation: oncogenes and those in charge of opinoids biosynthesis that promote the sickness known as crown gall, which consists in a continuous growth due to the lack of control at the cell cycle. The process of transformation by Agrobacterium requires the presence of several genetic elements: (1) The virulent genes from the chromosome of Agrobacterium (chv), (2) The T-DNA which is limited by the left and right borders (3) The virulent genes from the Ti (vir) plasmid that co...