Transcript Biochemical Pathways: Eduard & Hans Buchner

By: Haben M. & Cordelia E.
BACKGROUND
These 2 brothers were born in Munich,
Germany
 Their father was a professor of forensic
medicine
 Hans was the oldest of both
 He was a physician who researched
blood proteins that can destroy bacteria
 Eduard: chemist; researched yeast cells
along side Adolf von Baeyer
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What was already known?
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That food spoiled after a few days when
exposed to air
The fermenting agent comes from the air
The cause: bacteria
The theory of fermentation was first
developed by Louis Pasteur
He believed that fermentation was
physiological in yeast cells
In contrast Justin von Liebig, a chemist,
believed that the cause was a chemical
agent within the cell
The Experiment:
Hans Buchner worked along side his
younger brother by contributing the
study of anaerobic bacteria
 He discovered the blood serum could kill
bacteria,
 But this ability was useless if heated
 Anaerobic bacteria: bacteria that can
exist with limited or complete absence of
oxygen
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Summarize:
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Eduard Buchner used a pestle & mortar to
ground up yeast
Then extracted juices
The "dead" liquid fermented a sugar
solution, which formed carbon dioxide &
alcohol much like living yeasts.
The “non-living“ yeast behaves just like the
cells
It was then acknowledged that
fermentation is caused by an enzyme
Cell-free Fermentation:
Buchner continued Pasteur’s
discoveries
 Through a series of experiment he
discovered the enzyme: ZYMASE
 This enzyme catalyzes the reaction of
fermentation to produce C2H5OH and
CO2
 Proved that yeast cells were not needed
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Relation to cellular respiration:
Ferments glucose
 Produces ethanol and carbon dioxide in
the pyruvate stage
 Fermentation is an added cycle that
replaces the Krebs cycle
 There is no need for oxygen
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What was learned?
Zymase catalyses the breakdown of
glucose in the process of glycolysis
 Eventually slows down the process
 Yeast can breakdown sugars with or
without oxygen
 Enzymes can be extracted from yeast
 Final products: alcohol & carbon dioxide
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References:
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Eduard Buchner. (n.d.). Retrieved November 15,2010 from
http://www.nndb.com/people/227/000099927/
"Eduard Buchner - Biography". Nobelprize.org. 16 Nov 2010
http://nobelprize.org/nobel_prizes/chemistry/laureates/1907/buch
ner-bio.html
Cell- free fermentation. (n.d.). Retrieved November 15,2010 from
http://nobelprize.org/nobel_prizes/chemistry/laureates/1907/buch
ner-lecture.pdf
The background to Eduard Buchner's discovery. (n.d.) Retrieved
November 15, 2010 from http://www.jstor.org/pss/4330549
Zymase. (n.d.). Retrieved November 15, 2010 from
http://www.answers.com/topic/zymase
Eduard Buchner. (n.d.). Retrieved November 15,2010 from
http://www.britannica.com/EBchecked/topic/82903/EduardBuchner
Cellular Respiration & Fermentation. (n.d.). Retrieved November
16, 2010 from
http://biology.clc.uc.edu/Courses/bio104/cellresp.htm
THE END