jan 1, 1928 - Fredrick Griffith

Description:

Discovered how bacteria uses DNA to survive though experimenting on Streptococcus pneumoniae.

The experiment was injected into mice using 3 strains
-S-strain: deadly (contains capsules that protect the bacteria from the immune system)
-R-strain: not deadly (of lack of capsule)
-Heat-killed S-strain: not deadly (the bacteria is already dead)

it was discovered that combining both the heat-killed S-strain, and the R-strain became dangerous because DNA from the heat-killed S-train transfers to the R-strain, turning it into a the deadly S-strain. This process is called the transforming principle.

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