Klebs \ˈklāps\ , (Theodor Albrecht) Edwin (1834–1913), German bacteriologist. Klebs is notable for his work on the bacterial theory of infection. During the Franco-Prussian War he made one of the first comprehensive studies of the pathology and bacteriology of gunshot wounds. He investigated tuberculosis throughout his career, and in 1873 he successfully produced tuberculosis in cattle. He also did research on the bacteriology of malaria and anthrax. In 1883 he made his most important discovery: the causative organism of diphtheria, now known as the Klebs-Löffler bacillus.