Helicobacter pylori
John Robin Warren AC (born 11 June 1937, in Adelaide) is an Australian pathologist, Nobel Laureate and researcher who is credited with the 1979 re-discovery of the bacterium "Helicobacter pylori", together with Barry Marshall. The duo proved to the medical community that the bacterium "Helicobacter pylori (H. pylori)" is the cause of most peptic ulcers.