Secretion both DNA and proteins. It was discovered in "Agrobacterium tumefaciens", which uses this system to introduce the T-DNA portion of the Ti plasmid into the plant host, which in turn causes the affected area to develop into a crown gall (tumor). "Helicobacter pylori" uses a type IV secretion system to deliver CagA into gastric epithelial cells, which is associated with gastric carcinogenesis. "Bordetella pertussis", the causative agent of whooping cough, secretes the pertussis toxin partly through the type IV system. "Legionella pneumophila", the causing agent of legionellosis (Legionnaires' disease) utilizes a type IVB secretion system, known as the icm/dot (intracellular
White line disease White line disease White line disease (also known as seedy toe) is a fungal infection of the horse's hoof. As the name suggests, it attacks the white line, which connects the sole to the hoof wall. It is sometimes mistaken for hoof wall separation disease, but is not to be confused because it is not genetic nor as severe. White line disease changes the typical light color of the white line to a black or dark gray color. It may also give off a foul odor. Lameness is often not present unless the disease is advanced. The disease may locate