Science Fair Project Encyclopedia
Griffith was, in fact, trying to make a vaccine to prevent pneumonia infections in the epidemics after World War II. Griffith was trying to make a vaccine using two strains of the Stretococus pneumonia bacterium. The rough strain (R strain) did not cause pneumonia when injected into mice. The smooth strain (S strain) was deadly when injected, causing pneumonia and killing the mice in a day or two. When the S strain was heated to kill it and then injected into mice, it produced no ill effects in the subjects. However, when dead S coupled with live R were injected into the mouse, the mouse died. This is the first known example of bacterial transformation.
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details