Hans Christian Gram
|Hans Christian Gram|
Hans Christian Gram
13 September 1853|
14 November 1938 (aged 85)|
|Known for||Inventing the Gram stain|
|Doctoral advisor||Japetus Steenstrup|
Early life and education
Gram studied at the University of Copenhagen and was an assistant in botany to the zoologist Japetus Steenstrup. His study of plants introduced him to the fundamentals of pharmacology and the use of the microscope.
Gram entered medical school in 1878 and graduated in 1883. He travelled throughout Europe between 1878 and 1885. In Berlin, in 1884, he developed a method for distinguishing between two major classes of bacteria. This technique, the Gram stain, continues to be a standard procedure in medical microbiology.
The work that gained Gram an international reputation was his development of a method of staining bacteria, to make them more visible under a microscope. The stain later played a major role in classifying bacteria. Gram was a modest man, and in his initial publication he remarked, "I have therefore published the method, although I am aware that as yet it is very defective and imperfect; but it is hoped that also in the hands of other investigators it will turn out to be useful." A Gram stain is made using a primary stain of crystal violet and a counterstain of safranin. Bacteria that turn purple when stained are called 'Gram-positive', while those that turn red when counterstained are called 'Gram-negative'.
Gram was appointed professor of medicine at the University of Copenhagen in 1900. As a professor, he published four volumes of clinical lectures which became widely used in Denmark. He retired from the University of Copenhagen in 1923, and died in 1938.
- Gram, H.C. (1884). "Über die isolierte Färbung der Schizomyceten in Schnitt- und Trockenpräparaten". Fortschritte der Medizin (in German). 2: 185–189.
An English translation is in Brock, T.D. (1999). Milestones in Microbiology 1546–1940 (2 ed.). ASM Press. pp. 215–218. ISBN 1-55581-142-6.
A translation is also at Brock, T.D. "Pioneers in Medical Laboratory Science: Christian Gram 1884". Hoslink. Retrieved 2010-07-27.
- Jay Hardy. "Gram's Serendipitous Stain" (PDF). Retrieved 13 March 2016.