RECOGNITION OF BACTERIAL AVIRULENCE PROTEINS OCCURS INSIDE THE PLANT-CELL - A GENERAL PHENOMENON IN RESISTANCE TO BACTERIAL DISEASES

One of the recent exciting developments in the research area of plant- microbe interactions is a breakthrough in understanding part of the in itial signalling between avirulent Gram-negative bacteria and resistan t plants. For resistance to occur, both interacting organisms need to express matching genes, the plant resistance gene and the bacterial av irulence gene. The biochemical function of bacterial avirulence genes and the nature of the signal molecules recognized by the plant have be en a mystery for a long time. Recently, several laboratories have show n that bacterial avirulence proteins function as elicitors that are pe rceived within the plant cell.