Adolf Eduard Mayer (9 August 184325 December 1942) was a German

agricultural chemist Agricultural chemistry is the study of chemistry, especially organic chemistry and biochemistry, as they relate to agriculture—agricultural production (economics), production, the food processing, processing of raw products into foods and beverag ...

whose work on

tobacco mosaic disease ''Tobacco mosaic virus'' (TMV) is a positive-sense single-stranded RNA virus species in the genus '' Tobamovirus'' that infects a wide range of plants, especially tobacco and other members of the family Solanaceae. The infection causes characte ...

played an important role in the discovery of

tobacco mosaic virus ''Tobacco mosaic virus'' (TMV) is a positive-sense single-stranded RNA virus species in the genus ''Tobamovirus'' that infects a wide range of plants, especially tobacco and other members of the family Solanaceae. The infection causes characteri ...

and

virus A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsk ...

es in general. Mayer was born in 1843 into the family of a high school teacher in Oldenburg. His mother was a daughter of renowned German chemist

Leopold Gmelin Leopold Gmelin (2 August 1788 – 13 April 1853) was a German chemist. Gmelin was a professor at the University of Heidelberg He worked on the red prussiate and created Gmelin's test, and wrote his ''Handbook of Chemistry'', which over successi ...

. From 1860 to 1862 he studied mathematics and chemistry at the Karlsruhe Institute of Technology. In 1862 he enrolled at the

University of Heidelberg } Heidelberg University, officially the Ruprecht Karl University of Heidelberg, (german: Ruprecht-Karls-Universität Heidelberg; la, Universitas Ruperto Carola Heidelbergensis) is a public research university in Heidelberg, Baden-Württemberg, ...

, where in 1864 he graduated summa cum laude with a Ph.D. in chemistry, physics, and mathematics. In 1879, while Mayer held the position of the director of the Agricultural Experiment Station at

Wageningen Wageningen () is a municipality and a historic city in the central Netherlands, in the province of Gelderland. It is famous for Wageningen University, which specialises in life sciences. The municipality had a population of in , of which many ...

in the

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

, he was asked by Dutch farmers to study a peculiar disease affecting the

tobacco Tobacco is the common name of several plants in the genus '' Nicotiana'' of the family Solanaceae, and the general term for any product prepared from the cured leaves of these plants. More than 70 species of tobacco are known, but the ...

plant. Mayer published a paper in 1886 on the disease, which he named "mosaic disease of tobacco", and described its symptoms in detail. He demonstrated that the disease can be transmitted by using the sap from the affected tobacco plants as the inoculum to infect healthy plants. At the time, this disease was thought to be spread by very small

bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of prokaryotic microorganisms. Typically a few micrometr ...

toxin A toxin is a naturally occurring organic poison produced by metabolic activities of living cells or organisms. Toxins occur especially as a protein or conjugated protein. The term toxin was first used by organic chemist Ludwig Brieger (1849 ...

s, yet some years later the

(TMV) was shown to be the culprit. Mayer employed

optical microscopy Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultravio ...

to seek signs of fungi or bacteria in the infected sap, yet he did not find any, since the TMV is too small to be detected in an

optical microscope The optical microscope, also referred to as a light microscope, is a type of microscope that commonly uses visible light and a system of lenses to generate magnified images of small objects. Optical microscopes are the oldest design of microsc ...

. Mayer still concluded that the infectious agent was some sort of bacteria and erroneously claimed that he was able to obtain "clear filtrate" from the infected sap using filter paper in several repetitions. Filtration experiments with paper and finest porcelain

Chamberland filter A Chamberland filter, also known as a Pasteur–Chamberland filter, is a porcelain water filter invented by Charles Chamberland in 1884. It was developed after Henry Doulton, Henry Doulton's ceramic water filter of 1827. It is similar to the ...

s were replicated by Dmitry Ivanovsky in 1892 and

Martinus Beijerinck Martinus Willem Beijerinck (, 16 March 1851 – 1 January 1931) was a Dutch microbiologist and botanist who was one of the founders of virology and environmental microbiology. He is credited with the discovery of viruses, which he called "'' ...

in 1898, who showed that the infectious agent of the tobacco mosaic disease was in fact infilterable.

coined the term of "virus" to indicate a non-bacterial nature of the tobacco mosaic disease. In 1935, the tobacco mosaic virus was the first

to be crystallized. Despite the erroneous conclusion, Mayer's pioneer work on the tobacco mosaic disease served as an important step in the discovery of viruses and led to the foundation of the field of

virology Virology is the scientific study of biological viruses. It is a subfield of microbiology that focuses on their detection, structure, classification and evolution, their methods of infection and exploitation of host cells for reproduction, th ...

References

{{DEFAULTSORT:Mayer, Adolf 1843 births 1942 deaths German agronomists German biochemists German virologists Karlsruhe Institute of Technology alumni Heidelberg University alumni Wageningen University and Research faculty