ABSTRACT
Agrobacterium tumefaciens is a soil bacterium responsible for crown gall (the crown is the intersection of root and stem), a disease affecting dicotyledonous plants, which is manifested in uncontrolled division of cells at the site of infection and the development of a plant tumour. During the process of infection, complex molecular mechanisms are involved in the stable integration of a DNA fragment of bacterial origin into the plant genome. This natural mechanism of DNA transfer has been "domesticated" for biotechnological purposes and the co-culture of A. tumefaciens is today undoubtedly the most commonly used method of genetic transformation of plants. A few years ago, A. tumefaciens was also used for genetic transformation of yeasts and filamentous fungi, as well as human HeLa cells.
