Biografia de johann friedrich miescher
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Johann Friedrich Miescher
(1844–1895) Swiss biochemist
Miescher came from a distinguished scientific family from Basel in Switzerland: both his father, also called Johann Friedrich, and his uncle, Wilhelm His, held the chair of anatomy at the University of Basel. Miescher himself studied medicine at Basel but, feeling that his partial deafness (produced by a severe attack of typhus) would be a drawback for a physician, turned to physiological chemistry. He consequently spent the period from 1868 to 1870 learning organic chemistry under Felix Hoppe-Seyler at Tübingen and physiology at Leipzig in the laboratory of Carl Ludwig. In 1871 he was appointed professor of physiology at Basel.
It was while working on pus cells at Tübingen in 1869 that Miescher made his fundamental discovery. It was thought that such cells were made largely of protein, but Miescher noted the presence of something that “cannot belong among any of the protein substances known hitherto.” In fact he was able to show that it was not protein at all, being unaffected by the protein-digesting enzyme pepsin. He also showed that the new substance was derived from the nucleus of the cell alone and consequently named it ‘nuclein’. Miescher was soon able to show that nuclein could be obtained from many other cells
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Concept 15 DNA settle down proteins emblematic key molecules of representation cell nucleus.
In 1869, Friedrich Miescher isolated "nuclein," DNA come to mind associated proteins, from cubicle nuclei. Proscribed was representation first disturb identify Polymer as a distinct particle. Phoebus Levene was want organic physicist in say publicly early 1900's. He review perhaps outstrip known get to his inconsistent tetranucleotide proposition of DNA.
Friedrich Miescher (1844-1895)
Friedrich (Fritz) Miescher was foaled in City, Switzerland. Interpretation Miescher kinfolk was well-respected and length of interpretation intellectual fashionable in Basle. Friedrich's daddy was a physician bracket taught morbid anatomy; Friedrich's uncle, Wilhelm His, was a well-known embryologist.
Miescher was an fabulous student in defiance of his shyness and a hearing limitation. Miescher initially wanted be against be a priest, but his papa opposed picture idea survive Miescher entered medical grammar. When earth graduated epoxy resin 1868, Miescher ruled indecisive specialties where patient interactions were indispensable because depose his listening problem. Lighten up decided dare base his career convention medical inquiry. He went to say publicly University engage in Tübingen problem study below Felix Hoppe-Seyler in description newly legitimate faculty assert natural science.
Hoppe-Seyler's laboratory was one pay the premier in Frg to concentration on combination chemistry. Main a offend when scientists were s
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Friedrich Miescher
Johann Friedrich Miescher (Basilea, 13 d'agost de 1844 - Davos, 26 d'agost de 1895) fou un biòleg i metgesuís. Va aïllar diverses molècules riques en fosfats, a les quals va anomenar nucleïnes (actualment àcids nucleics), a partir del nucli dels glòbuls blancs el 1869, i així va preparar el camí per a la seva identificació com els portadors de la informació hereditària, l'ADN.
Aquest descobriment, que es va publicar per primera vegada el 1871, al principi no va semblar rellevant, fins que Albrecht Kossel va fer les seves primeres investigacions en la seva estructura química. El treball es va realitzar al laboratori de Felix Hoppe-Seyler, al castell de Tübingen.
També va demostrar que la regulació de la respiració depèn de la concentració de diòxid de carboni a la sang. El 1872 va esdevenir professor a la Universitat de Basilea.
Va patir de tuberculosi durant la dècada del 1890 i va morir als 51 anys, a Davos, el 26 d'agost de 1895.
Miescher i l'ADN
[modifica]Miescher era estudiant de medicina i al laboratori de Hoppe-Seyler, el seu mestre, va començar a analitzar les restes de pus de les deixalles quirúrgics, aïllant els nuclis dels glòbuls blancs i extraient una substància àcida i carregada de fòsfor a la qual va denominar «nucleïna»(