OSWALD AVERY: BIOGRAPHY AND EXPERIMENTS - CULTURE VOCABULARY - 2025

Oswald Avery (1877–1955) was a renowned United States bacteriologist from Canada, known for determining that DNA is the molecule responsible for inheritance, allowing the establishment of the bases that defined the science of molecular genetics.

In addition, the work he carried out with numerous scientists, contributed to the understanding of the chemical processes of immunological processes.

Oswald Avery at the Rockefeller Institute for Medical Research

Despite the importance of Avery's work to the advancement of medicine, there is not a great deal of information regarding his personal life. He was nominated several times to be awarded a Nobel Prize for his research, but failed to obtain such an award. On the other hand, the lunar crater called "Avery" was named in his honor.

Biography

Early years

Oswald Theodore Avery was born on October 21, 1877, in the city of Halifax, located in Nova Scotia, Canada. He was the son of Joseph Francis Avery, a Baptist minister, and Elizabeth Crowdy, about whom there is little information.

Both parents were British and it is theorized that their parents had emigrated from Great Britain approximately four years before having Oswald.

In addition, there are references that the bacteriologist was born and raised in a house located in Halifax, Canada, along with his other two brothers. At age 10 his family moved to the Lower East Side of New York after his father felt the need to do a work of God in North America.

Various sources assure that from the age of 12 Oswald Avery began to play music with his brother; the hobby led him to become a talented musician worthy of a scholarship. However, some biographical data indicate that he did not use such a benefit.

On the other hand, when Avery was 15 years old, he lost his brother to tuberculosis and his father to kidney disease, which was a difficult time during his youth.

Studies

Avery attended an elementary school in New York, a degree he obtained before he was 16 years old in 1893.

Some handle the hypothesis that Oswald Avery began studying music at around 16 years of age at an academy. However, his interests changed to the point of leaning towards medicine, a career that he studied years later, in 1900.

Oswald Avery studied medicine at Columbia University College of Physicians and Surgeons, located in New York City, USA. Finally, he obtained a medical degree in 1904.

Within a few years of practicing the profession he studied at Columbia University, Avery began to pay special attention to bacteriological research.

It is believed that the suffering of the patients he cared for for incurable diseases motivated him to specialize in the area of ​​microbiology, with which he tried to contribute to stop the advance of microorganisms that caused the death of people.

Some hypothesize that Oswald Avery gradually specialized in thanks to his studies of the bacteriological process of milk before and after pasteurization.

Start of your career as a bacteriologist

What little information there is regarding the first steps in the professional world of medicine indicates that when Avery was in his 30s, in 1907, he became assistant director of the Hoagland Laboratory, located in Brooklyn, New York.

In his work he devoted himself to teaching students and increasing their knowledge of modern chemical and bacteriological methods, which gave him the habit of carrying out experimental procedures with great care and meticulousness.

During his work he conducted studies of fermented dairy products such as yogurt, as well as their role in controlling harmful intestinal bacteria in people.

Consulted sources affirm that Avery got to publish at least nine articles in academic journals, until in 1913 one of his publications interested the director of the Rockefeller Institute Hospital in the United States.

I work at the Rockefeller Institute Hospital

In 1913, Avery joined the Rockefeller Hospital Institute team in the United States. In that place, he began the corresponding studies of Streptococcus pneumoniae, the bacterium that causes lobar pneumonia.

For this, the doctor and his co-workers managed to isolate a molecule that they found in the blood and urine of people who suffered from the disease caused by the bacteria. The work revealed that it was a complex carbohydrate that was called ¨polysaccharide¨, which constitutes the capsular envelope of the pneumococcus.

Through a series of subsequent studies in which they found that the polysaccharide composition of these envelopes could vary, Avery was able to determine the different types of pneumococcus that exist.

In addition, he discovered that the polysaccharide could stimulate the production of antibodies that would allow an immune response. The finding was an important step in the history of medicine, because he was the first person to show that a substance other than a protein could be.

Ultimately, Avery dedicated the rest of his life to studying and researching the bacteria that cause pneumonia, a disease that killed thousands of people in the United States during that time.

American citizen

Despite spending his entire life in the United States, Oswald Avery was still not an American citizen at 40 years of age. The doctor is believed to have attempted to join the officer post in the US Army Medical Corps; however, it was rejected by the authorities.

Later, during the development of World War I, he attempted to enter the medical corps by running for the lowest rank. His second attempt to belong to the medical corps was successful, so the authorities of the country formally naturalized him as an American citizen.

The experiment that prompted Avery's research

For many years scientists knew that there were genes responsible for transmitting information through generations; however, they believed that these were protein-based.

British geneticist Frederick Griffith worked with strains of Streptococcus pneumoniae: one that was surrounded by a polysaccharide (carbohydrate) capsule that contained a virus, and another that had no capsule and no virus.

After a series of analyzes and investigations, Griffith noticed that the strain containing the virus could convert the other strain, which did not contain it, into an agent capable of causing the disease.

This transformation could be transmitted to successive generations of bacteria. Back then, Griffith used mice to conduct his experiments.

Discovery

Avery was recognized for the studies he conducted regarding Streptococcus pneumoniae. However, one of the works that most earned him to be considered as a vital figure for the advancement of medicine at the time was the discovery that DNA was the molecule responsible for genetic inheritance.

His work started from the investigations carried out by the British geneticist that served as an impulse.

Last years

Despite the importance of the discovery by Oswald Avery and his team, as well as the numerous investigations they carried out, some say that he was never awarded a Nobel Prize.

On the other hand, there is little information regarding Oswald Avery's personal life. However, sources indicate that the bacteriologist never abandoned his love of music. Nor did he get married or have children.

Several sources indicate that Avery died on February 20, 1955 in Nashville, the capital of Tennessee, United States, after suffering from liver cancer.

Experiments

Transforming principle

In 1932, almost 20 years after joining the group that allowed him to make the pneumococcal discoveries, Oswald Avery began to turn his attention to the geneticist Frederick Griffith's experiment, especially since it was closely related to pneumonia.

Avery was incredulous about the geneticist's results; However, a researcher in his laboratory named Martin Dawson replicated the experiment carried out by Frederick Grifth and corroborated the results previously obtained by the microbiologist.

After the results obtained by the British, Avery together with other scientists made the determination to establish the chemical nature of this substance that allowed the transformation to take place, which was described by professionals as the transforming principle.

For several years they made several theories about the transforming agent without reaching positive results.

Some theories indicate that the work to arrive at a decisive result was slow, because Avery had other important studies and, in addition, he stayed away from the studies in his laboratory due to illness.

It is believed that starting in 1936, the bacteriologist began to hypothesize that a nucleic acid may have been responsible for the transforming principle.

DNA

With the help of Canadian Colin MacLeod, Avery implemented laboratory techniques that increased confidence in the results.

In 1941, scientists ruled out that the transforming agent had proteins and lipids. Shortly afterward MacLeod withdrew from the investigation, but kept his focus on its progress.

After MacLeod's departure, American Maclyn McCarty joined Avery's investigations. It is believed that after conducting several chemical tests, man established that the transforming principle was generated thanks to deoxyribonucleic acid.

Deoxyribonucleic acid, known by its abbreviation as DNA, is a molecule made up of a complex molecular structure that can be found in all prokaryotic and eukaryotic cells, as well as in many viruses.

It was discovered in 1869; however, its role in genetic inheritance was proven in 1943 by Oswald Avery and his team.

In 1944, Oswald Avery, Maclyn McCarty and Colin MacLeod took a new step that marked a before and after in the history of medicine.

After the analyzes, Avery and his team published a publication with the discovery of DNA as a genetic material that induces inherited changes in bacteria. This discovery was an important advance in the development of immunochemistry.

Skepticism about the discovery

At first the finding was taken with some caution by the other experts, because they were convinced that proteins were responsible for hereditary information.

Despite this, the research carried out by both Avery and his colleagues obtained a marked relevance, so the discovery was accepted and its role in the contribution to genetics was recognized.

Austrian chemist Erwin Chargaff was one of the few professionals who almost immediately supported the studies of Avery and his team. Theories suggest that he was one of the most important scientists in establishing the role of DNA in genetics.

Hershey-Chase experiment

Various sources argue that the discovery by Avery, McCarty and MacLeod was supported by the American biologist Martha Chase and the bacteriologist Alfred Hershey, who conducted the Hershey-Chase Experiment in 1952.

The work required a series of experiments in which they used a bacteriophage (understood as a virus that infects bacteria) to analyze the behavior of deoxyribonucleic acid.

The results obtained from the Hershey-Chase Experiment allowed to confirm that DNA is the basis of genetic material. The investigative work is presumed to have earned Hershey a Novel Award.

A year later, in 1953, James Watson and Francis Crick discovered the structure of DNA, as well as how it replicates. Avery managed to see the discovery.

The theory is that the Hershey-Chase Experiment led to the discovery by Watson and Crick of the helical structure of DNA, which led to the birth of modern genetics and molecular biology.

References

1. Oswald Avery, Portal Biography, (2014). Taken from biography.com
2. Oswald Avery. American Bacteriologist, editors of Enclyclopedia Britannica, (2018). Taken from britannica.com
3. DNA, editors of Enclyclopedia Britannica, (2018). Taken from britannica.com
4. Oswald Avery, English Wikipedia, (nd). Taken from wikipedia.org
5. Oswald Avery, Portal Famous Scientists, (nd). Taken from famousscientists.org
6. The Oswald T. Avery Collection, Portal US National Library of Medicine, (nd). Taken from profiles.nlm.nih.gov