10/11/2013 · Frederick Griffith Discovers ..

Today, we know that the "transforming principle" Griffith saw was the of the III-S strain bacteria. While the bacteria had been killed, the DNA had survived the heating process and was taken up by the II-R strain bacteria. The III-S strain DNA contains the genes that form the shielding polysaccharide part from attack. Armed with this gene, the former II-R strain bacteria were now protected from the host's immune system and could kill the host. The exact nature of the transforming principle (DNA) was confirmed in the experiments done by Avery, McLeod and McCarty and by .

Frederick Griffith by Abby Stettner on Prezi

Griffith's experiment, was an experiment done in 1928 by Frederick Griffith

Frederick Griffith Attended University ..

For more about this topic see in the link section "The Nobel Prize Omission"

Before you start, please pay notice that these experiments can be dangerous since you will have to experiment with bacteria that can be infectious and other chemicals, materials and apparatus that can be dangerous for your health.

As a rule: this experiment should be performed under the supervision of professionals familiar with chemical, biomedical and laboratory safety procedures.

Frederick Griffith vs Oswald Avery comparison

Griffith was surprised to find in his experiments that mice injectedwith a mixture of heat-killed S-strain and live but nonvirulent R-strainproduced lethal results. In fact, Griffith discovered living forms of theS-strain bacteria in the infected mice !

Accomplishments Graduated from Liverpool University His experiment lead him to fame, enabling his discovery of the Transformation Principle.

Frederick Griffith - Gpedia, Your Encyclopedia

In 1928 Frederick Griffith, in a series of experiments with (bacterium responsible for pneumonia), witnessed a miraculoustransformation. During the course of his experiment, a living organism(bacteria) had changed in physical form.

Frederick Griffith and Oswald Avery were key researchers in the discovery of DNA

Isolating hereditary material: Frederick Griffith, ..

Oswald Avery, Colin McCleod, and Maclyn McCarty (1934-1944) at the RockefellerInstitute, building on Griffith's work, showed that only DNA could causethe transformation. They isolated a cell-free extract from the S-strainbacteria and were able to transform living R-strain into a culture containingboth S-strain and R-strain cells. The purified extract contained Griffith's"transforming principle". Through biochemical testing, they showedit to be deoxyribonucleic acid (DNA).

What result from Griffith's experiment suggested that the cause of pneumonia ..

(2008) Isolating hereditary material: Frederick Griffith, ..

Young Life
Frederick Griffith
Attended University of Liverpool
Class of 1901
Studied genetics
Worked at:
Liverpool Royal Infirmary
Thompson Yates Laboratory
Royal Commission on Tuberculosis
In 1910, began working for the English government
Professional Life - Jobs
The British were buying things sparingly
Griffith was, therefore, forced to make do with what he had been given
War was expected - they didn't want to continue spending their money
Working for British Government
During World War II, Griffith worked as a British Medical Officer
World War II
Not many friends
The friends he did have would often describe him as a "jolly fellow"
What was Griffith like?
He had a house in Sussex, England
Outside of the Lab, What Were his Hobbies?
High pneumonia epidemic
Create a vaccine to end pneumonia.
He wanted to find a way to easily end pneumonia and find out what exactly caused it.

Frederick Griffith 1928 English microbiologist Dr Griffith was working with two from LS 3 at UCLA

During the 1920s Frederick Griffith studied the difference between ..

Griffith used two of (which infects ), a type III-S (smooth) and type II-R (rough) strain. The III-S strain covers itself with a capsule that protects it from the host's , resulting in the death of the host, while the II-R strain doesn't have that protective capsule and is defeated by the host's immune system. A German bacteriologist, , had discovered the three pneumococcal types (Types I, II, and III) and discovered the Quellung reaction to identify them in vitro. Until Griffith's experiment, bacteriologists believed that the types were fixed and unchangeable, from one generation to another.