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Meinsicher
Meinsicher was the first to identify DNA as a distinct molecule. By taking the puss off bandages from a near-by-clinic, Meinsicher was able to identify nuclein. He began isolating the nuclein and realized that the new molecule included hydrogen, oxygen, nitrogen and phosphorus and there was an unique ratio of phosphorus to nitrogen. Over time, Meinsichers discoveries would be paired with others to create the view we now have on DNA. -
Franklin
Originally,Franklin and Watson worked together but after her critical reviews of his colleagues, Watson separated himself from Franklin. This caused her to change where she studied her field. During Franklins move, Watson came into possession of "photo 51," a detailed x-ray image of a double helix shaped strand of DNA. While Franklin moved onto the virology field, Watson ad Crick used her notes and "photo 51" to prove that they were correct in stating that DNA is in the shape of a double helix. -
Chargaff
Usingpaper chromatography and UV spectrophotometry, Chargaff built on the discoveries of Oswald Avery to show that DNA had almost equal amounts of adenine, thymine, cytosine, and guanine. This was later to be formalized as "Chargaff’s Rule". Chargaff also advised Watson and Crick to pair adenine and thymine together, and to pair with cytosine and guanine together. Many believe that had he not influenced Watson and Crick, we would not have the image of DNA as a double helix that we do today. -
Hershey and Chase
Using a bacterial virus called phage, Hershey and Chase demonstrated that DNA is the genetic material within cells. They created radio active versions of the protein coat and kept the DNA normal. After infecting a bacterial cell, the phage released its genetic materiel (DNA). After shaking, the empty radio active coats were released. However, the virus proteins that grew within the bacterial cell were normal. Without Hershey and Chase, we would not know how genetic material in cells works. -
Watson and Crick
Watson and Crick are known for establishing the shape of DNA, which was the double helix. they started out by placing cardboard cut outs that represented separate nitrogenous bases. They could not figure out how chargaffs rule applied while using this method. It was not until they took Donhues suggestion and placed the complementary bace pairs together did they identify that the shape of DNA strands is a "twisted ladder" shape that we now call a double helix. -
Bibiliography
Nature.com. Macmillan Publishers, Web. 17 Jan. 2017"Rosalind Franklin: Biography & Discovery of DNA Structure." LiveScience. Purch, n.d. Web. 17 Jan. 2017.
"Erwin Chargaff Biography." Totally History Erwin Chargaff Comments. Totallyl History, Web. 19 Jan. 2017.
"Chargaff's Rule." Savannah " The Cell Leader". Weebly, Web. 19 Jan. 2017.
"Concept 15 DNA and Proteins Are Key Molecules of the Cell Nucleus." Friedrich Miescher :: DNA from the Beginning. DNA Learning Center, Web. 21 Jan. 2017. -
Meselson and Stahl
Meselson and Stahl established the hypothesis of Semi-conservative cellular division. Using nitrogen, they modified the original DNA to be very heavy. By utilizing centrifugation to separate light and heavy DNA Meselson and Stahl proved the conservative and dispersive cellular division theories wrong. By conducting "the most beautiful experiment in biology," Meselson and Stahl built upon all previous geneticists in order to revolutionizes Genetics. -
Bibliography continued
"Wordnik." Wordnik.com. Wordnik, n.d. Web. 21 Jan. 2017.
"Structural Biochemistry." Nucleic Acid/DNA/Replication Process - Wikibooks, Open Books for an Open World. Wikibooks, n.d. Web. 21 Jan. 2017.
"Hershey+and+Chase+Experiment." Hershey and Chase Experiment. Margraw-Hill Companies, Inc., Web. 21 Jan. 2017.
