Martinus Beijerinck

Martinus Willem Beijerinck (1851-1931) was a Dutch microbiologist and botanist, one of the founders of virology and environmental microbiology. In 1898 he published research on tobacco mosaic disease showing that its infectious agent passed through filters that trapped bacteria; rather than call it a bacterium he coined the term virus, describing it as contagium vivum fluidum, a living fluid-like entity. Later scientists showed viruses were particulate rather than liquid, but his insight opened the field of virology. He also investigated nitrogen fixation, discovered bacterial sulfate reduction, and developed the enrichment culture technique, still central to microbiology. His legacy has been less prominent than contemporaries such as Pasteur and Koch, in part because his work centered on agricultural and plant systems rather than human disease.