This Week in Science History: 4-10-10

By Peter Dearden 05/10/2010 2


This week in Science History
Megan Leask, PhD Student, Laboratory for Evolution and Development

It’s Nobel week!

Michael Smith – died 4th of Oct 2000 (born 26 Apr 1932)

British-born Canadian biochemist who won (with Kary B. Mullis, inventor of PCR) the 1993 Nobel Prize for Chemistry for his development of a technique called oligonucleotide-based site-directed mutagenesis. This technique enabled researchers to introduce specific mutations into genes and, thus, to the proteins that they encode. The prize recognized his groundbreaking work in reprogramming segments of DNA, the building blocks of life. His work launched a new era in genetics research.

Prion discovery leads to Nobel Prize for Stanley Prusiner

Tonsil biopsy in variant CJD. Prion Protein immunostaining (Image: Sbrandner, Wikimedia Commons)

In 1997 on the 6th of October, American biology professor Stanley B. Prusiner won the Nobel Prize for medicine for discovering “prions,” described as “an entirely new genre of disease-causing agents.” Prusiner’s work proposed an explanation for the cause of bovine spongiform encephalopathy (“mad cow disease”) and its human equivalent, Creutzfeldt-Jakob disease. In this work, he coined the term prion, which comes from the words “proteinaceous” and “infectious,” to refer to a previously undescribed form of infection due to protein misfolding.

Prions propagate by transmitting a mis-folded protein state: so as with viruses the protein cannot replicate by itself. Instead, when a prion enters a healthy organism the prion form of a protein induces pre-existing normal forms of the protein to convert into the rogue form. Since the new prions can then go on to convert more proteins themselves, this triggers a chain reaction that produces large amounts of the prion form.

Franklin William Stahl – Born 8 Oct 1929

Franklin William Stahl is a U.S. geneticist who, in 1958, (with Matthew Meselson) elucidated the mode of replication of deoxyribonucleic acid (DNA) a double-stranded helix that dissociates to form two strands, each of which directs the construction of a new sister strand. They grew E. coli on media (food) that contained the heavier isotope of nitrogen-15 causing all of their DNA to be heavy. They switched the E. coli to media that contained normal nitrogen and then analyzed the DNA after each generation. After one generation, all of the DNA was medium-weight. Thus one strand of the double helix was heavy and one strand was light. After two generations, half of the DNA was medium-weight and half was normal light-weight DNA.

Maurice Hugh Frederick Wilkins – Died 5 Oct 2004 (born 15 Dec 1916)

Photo 51, an historic X-ray diffraction image of DNA (Image: Rosalind Franklin)
Photo 51, an historic X-ray diffraction image of DNA (Image: Rosalind Franklin)

Maurice Hugh Frederick Wilkins was a biophysicist, whose X-ray diffraction studies of deoxyribonucleic acid (DNA) were significant in the determination of the molecular structure of DNA accomplished by James Watson and Sir Francis Crick. For this work the three scientists shared the 1962 Nobel Prize for Physiology or Medicine. Wilkins was born in Pongaroa, north Wairarapa, New Zealand, his family moved to Birmingham, England when he was 6.


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