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1 ene 1929 año - Frederick Griffith: Bacterial Transformation

Descripción:

In 1929, Griffith conducted experiments with Streptococcus pneumoniae bacteria. He was originally trying to develop a vaccine against pneumonia, but ended up with a way to identify genetic material.

In his experiment, he used "R" (nonvirulent) and "S" (highly virulent) strains of bacteria. Through heating of the S strain of the bacteria he discovered that it's virulence was destroyed. He found that when injected with heat-killed S bacteria and living R bacteria, mice had died which was surprising because they where fine when the strains were injected separately.

This experiment led him to the hypothesis that a chemical component from the virulent S strain had transformed the R strains into a more virulent S form.

Today, looking back at this experiment we know that after being heat-treated, DNA molecules can re-nature, and that bacteria can take up DNA from the environment by a process that we refer to transformation.

Source: https://www.nature.com/scitable/nated/article?action=showContentInPopup&contentPK=336

Añadido al timeline:

29 nov 2018
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fecha:

1 ene 1929 año
Ahora mismo
~ 96 years ago

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