In this biography
Quick facts
- Born
- 4 December 1908
- Died
- 22 May 1997
- Birthplace
- Owosso, MI, USA
- Country
- United States
- Nationality
- Not independently established
- Known for
- Research on phage genetic structure and the 1952 component-labelling experiments with Martha Chase
Why this life matters
Research on phage genetic structure and the 1952 component-labelling experiments with Martha Chase
Timeline
Key moments
Birth
Alfred Hershey was born in Owosso, MI, USA.
Hershey–Chase paper
Published component-labelling experiments with Martha Chase.
Nobel recognition
Received Nobel recognition for the work described in the official award record.
A bacteriologist’s research training
Alfred Day Hershey was born in Owosso, Michigan, in 1908. He studied at Michigan State College, receiving his bachelor’s degree in 1930 and doctorate in 1934. He then worked in bacteriology at Washington University School of Medicine, remaining there until 1950. His career developed around viruses that infect bacteria, a system that allowed experimental questions about infection, growth and inheritance to be investigated with relatively simple biological material. The resulting programme connected microbiological technique with the emerging field of molecular genetics.
Building a phage programme at Cold Spring Harbor
Hershey joined the Carnegie Institution’s Department of Genetics at Cold Spring Harbor in 1950 and became director of its Genetics Research Unit in 1962. The phage research community included Max Delbrück, Salvador Luria and many other investigators developing genetic and quantitative approaches. Different strains, crosses and physical measurements supplied complementary information about viral organisation. Hershey’s later lecture describes work on the physical properties of phage DNA, showing that his contribution extended beyond one celebrated experiment on infection.
Martha Chase and the components of infection
Hershey and Martha Chase’s 1952 paper compared the behaviour of labelled phage material during infection. Sulfur-associated protein and phosphorus-associated material did not remain in the same fractions after infected bacteria were agitated and separated. The results supported the entry of most phage DNA while much of the coat remained outside. The original paper stated its limits explicitly rather than claiming to identify every possible entering molecule. Crediting both authors and naming the experimental system preserves the specific nature of the finding.
DNA growth as a continuing question
A 1953 paper investigated the economy of nucleic acids during T2 growth, including a DNA pool later incorporated into phage. Hershey continued studying genetic organisation and physical DNA properties through further collaborations. He shared the 1969 Nobel Prize in Physiology or Medicine with Delbrück and Luria for discoveries concerning viral replication and genetic structure. He died in 1997. His career helped make viruses experimental tools for investigating how genetic material is organised, transferred and used, with successive studies answering different parts of that larger problem.
Quick answers
Frequently asked questions about Alfred Hershey
- Who co-authored the 1952 experiment?
- Martha Chase and Alfred Hershey jointly authored the original paper.
- Was Hershey’s work limited to tracing DNA entry?
- No. His programme also investigated viral growth, genetic organisation and the physical properties of phage DNA.
Keep exploring
Lives connected to this story
- Seymour Benzer
Compare two phage programmes that used different experimental properties to investigate genetic material.
- Francis Crick
Compare component-tracing evidence with Crick’s later principles about sequence information.
Sources and further reading
Explore the evidence
These references support the biography and offer further reading. Official records, first-person accounts and independent reporting provide different perspectives; image records document attribution and licensing.
- 1. Alfred Hershey and Martha Chase / Journal of General Physiology, 1952Independent functions of viral protein and nucleic acid in growth of bacteriophage
The paper’s original restriction on chemical inference is retained; DNA entry and the complete mechanism of viral growth are not treated as identical endpoints.
- 2. Alfred Hershey / Journal of General Physiology, 1953Nucleic acid economy in bacteria infected with bacteriophage T2
- 3. Nobel Prize OutreachAlfred Hershey — Nobel lecture
- 4. Nobel Prize OutreachAlfred Hershey — Facts
- 5. Nobel Prize OutreachAlfred Hershey — Biographical
