General Information: This strain was isolated from an almond tree in California. Causal agent of citrus variegated chlorosis. This organism was first identified in 1993 as the causal agent of citrus variegated chlorosis, a disease that affects varieties of sweet oranges. Other strains of this species cause a range of diseases in mulberry, pear, almond, elm, sycamore, oak, maple, pecan and coffee which collectively result in multimillion dollar devastation of economically important plants. It does not contain a type III secretion system, but possesses genes for a type II secretion system for export of exoenzymes that degrade the plant cell wall and allow the bacterium to colonize the plant xylem. The cell produces an exopolysaccharide that is similar to the xanthan gum produced by Xanthomonas campestris pv. campestris.