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DNA Timeline

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Pragatheesh Sivasegaram

on 13 December 2013

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Transcript of DNA Timeline

DNA Timeline
1928 Frederick Griffith
Studied pathology of Streptoccus Peumoniae
Performed studies on mice of this bacterium
Proposed that some unknown "principle" had transformed the harmless R strain of Diplococcus to the virulent S strain.
1944 Oswald Avery, Colin Macleod, Macelyn McCarthy
Developed methods to isolate and chemically characterize the transforming principle
Published a study with a supported hypothesis, that DNA was hereditary
Reported that they had purified the transforming principle in Griffith's experiment

1952 Alfred Hershey & Martha Chase
Used phages in which the protein was labeled with 35S and the DNA wit 32P for the final proof that DNA is the molecule of heredity
Suggested that only DNA is required for viral replication
Also suggested that most of the labeled protein doesn't enter the cells but remains attached to the bacterial cell membrane
1951 Rosalind Franklin
Obtained sharp X-ray diffraction photographs of DNA
Explained how structure lends itself to replication
Contributed to the study of the "double helix" shape of the DNA

1869 Friedrich Miescher
Obtained first crude purification of DNA
Showed that DNA is fundamentaly differed from proteins
Termed his finding a “nuclein”
1908 Archibald Garrod
Proposed that some human diseases are due to "inborn errors of metabolism" that result from the lack of a specific enzyme.
Garrod derived that alkaptonuria is a recessive disorder
First to propose the idea that diseases were "inborn errors of metabolism."
1909 Phoebus Levene
Studied structure and function of nucleic acids
Levene published over 700 original papers and articles on the chemical structures of many biochemicals
Made the tetranucleotide theory of DNA
1866 Gregor Mendel
Had experiments with cross-pollination of peas
He deduced the existence of discrete hereditary units (genes)
Genes were present in pairs in the pea plant and that the pairs separated during gamete formation
Conducted studies on mold and the substance that kills bacteria in the mold
Tested mold on other harmful bacteria and concluded that mold was non-toxic
Discovered penicillin
1922 Alexander Flemming
1941 Edward Tatum and George Beadle
Irradiated the red bread mold, Neurospora
Proved that the gene produces its effect by regulating particular enzymes
Confirmed that genes direct the manufacture of proteins that control the basic metabolic functions
1959 Arthur Kornberg

Purified DNA polymerase I from E. coli, the first enzyme that made DNA in a test tube
Discovering the means by which deoxyribonucleic acid (DNA) molecules are duplicated in the bacterial cell
Discovered the mechanisms in the biological synthesis of deoxyribonucleic acid
1950 Erwin Chargaff
Discovered a one-to-one ratio of adenine to thymine and guanine to cytosine in DNA samples from a variety of organisms
Reported that DNA composition varies from one species to another
Found a peculiar regularity in the ratios of nucliotide bases, which later turned into "Chargaff's Rules"
1983 Barbara McClintock

Her work on the cytogenetics of maize led her to theorize that genes are transposable
Suggested that genes could move on and inbetween chromosomes
1976 Allan Maxam and Walter Gilbert
Had deciphered the genetic code and could spell out the sequence of amino acids in proteins
1953 James Watson and Francis Crick
Solved the three-dimensional structure of the DNA molecule
Used Franklin's X-Ray's of DNA, without her permission
1960 Sydney Brenner
One of the past century's leading pioneers in genetics and molecular biology
New understanding of the evolution of vertebrates
Established the existence of messenger RNA and demonstrated how the order of amino acids in proteins is determined
1958 Matthew Meselson and
Frank Stahl
Used isotopes of nitrogen to prove the semiconservative replication of DNA
Did experiments on the replication of DNA
Meselson and Stahl model was created
1968 Reiji Okazaki
Exposed the replicating DNA to short pulses
1972 Stanley Cohen and Herbert Boyer
Showed that a recombinant DNA molecule can be maintained and replicated in E. coli
Produced the first recombinant DNA molecules
1977 Fred Sanger
Developed the chain termination (dideoxy) method for sequencing DNA
Determining the structure of the hormone insulin
1996 K. Mullis, Wilmut and Campbell
Published a paper describing the polymerase chain reaction (PCR), the most sensitive assay for DNA yet devised
First to create a clone, Dolly the sheep
2001 Gerald Smith and Fred Hutchinson
Distinguished contributions to our understanding of the genetics and enzymology of homologous recombination
Understood DNA break repair and meiosis
2010 Elanie Mardis
Helped create methods and automation pipelines for sequencing the human genome
Institute's efforts to explore next generation and third generation sequencing technologies
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