Barry Marshall
In 2005 Barry J. Marshall and J. Robin Warren were awarded the Nobel Prize for Physiology or Medicine in recognition of their 1982 discovery that a bacterium, Helicobacter pylori, causes one of the most common and important diseases of mankind, peptic ulcer disease.
Barry Marshall met Robin Warren, a pathologist interested in gastritis, during internal medicine fellowship training at Royal Perth Hospital in 1981. The pair studied the presence of spiral bacteria in association with gastritis. The following year (1982), Helicobacter pylori was cultured for the first time and they developed their hypothesis related to the bacterial cause of peptic ulcer and gastric cancer.