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

What was already known?  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

Summarize:  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 C 2 H 5 OH and CO 2  Proved that yeast cells were not needed

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

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

References:  Eduard Buchner. (n.d.). Retrieved November 15,2010 from  "Eduard Buchner - Biography". Nobelprize.org. 16 Nov ner-bio.html ner-bio.html  Cell- free fermentation. (n.d.). Retrieved November 15,2010 from ner-lecture.pdf ner-lecture.pdf  The background to Eduard Buchner's discovery. (n.d.) Retrieved November 15, 2010 from  Zymase. (n.d.). Retrieved November 15, 2010 from  Eduard Buchner. (n.d.). Retrieved November 15,2010 from Buchner Buchner  Cellular Respiration & Fermentation. (n.d.). Retrieved November 16, 2010 from

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