Transcript Gustave Embden, Otto Meyerof and Jakub Parnas

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Was a prominent Jew-Polish–Soviet biochemist
Contributed to the discovery of the Embden–Meyerhof–Parnas pathway
His major work was the study of the mechanisms of carbohydrate metabolism
in muscle tissue
He discovered the process of phosphorolysis
Contributed to the analysis of Glycolysis
He also studied the metabolism of animals tissues
He used the rabbit in this case
He injected L(+/)and D (-) lactic acids to rabbits and analyzed its content
in particular organs like muscles and urine
Was able to prove that L and D forms of lactate are differently
metabolized
He concluded that L (+) lactic acid is quickly removed from tissues,
whereas D(-) lactate is extremely slowly metabolized and its toxic
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Did an experiment on the connection between the
breaking down of glycogen and lactic acid formation
Did the experiment on tissues homogenate and on
perfused organs
Him and Wagner performed the experiment on resting
and working isolated frog muscle in oxidative and
anaerobic conditions
Their result concluded that the decrease of carbohydrate
content in working muscles is accompanied by lactate
formation whereas in anaerobic conditions much less
lactate is present, less is formed, or is metabolized
further
*German biochemist born in 1884 and died in 1951
* In 1919 He showed that during muscle contraction
where oxygen is not present ,glycogen is converted
to lactic acid
 *Furthermore, he showed in the presence of oxygen
a small amount of lactic acid is broken down into
Carbon dioxide and water
 * In 1925 he extracted the group of enzyme that help
in the conversion of glycogen to lactic acid from
muscle
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* He studied metabolism of sea-urchin eggs
* He found a coenzyme of alcoholic fermentation
*studied the respiration of killed cells
* He discovered a co-enzyme of respiration
* Meyerhof showed that the unsaturated fatty acids in the cell are
oxidized with the help of the sulphydryl group
* He extracted from the muscle of a frog the enzymes that convert
glycogen to lactic acid
* observed that in the absence of oxygen in the muscle, lactic acid
appears slowly in the relaxed state and rapidly in the active state, and
that this lactic acid disappears again in the presence of oxygen
*concluded that oxygen is only involved in the relaxed state of a
muscle
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German biochemist
*Carried studies on Carbohydrate metabolism and
muscle contraction
* He was the first to find a connection between the steps
of conversion of glycogen to lactic acid
*He conducted his studies mostly in living organisms
especially in organs such as the liver
*He studied the metabolic processes in liver tissues
* From his studies on liver tissues he concluded that the
organ plays a significance role in metabolism
* His conclusion led him to further studies that led to the
researches of normal sugar metabolism and of diabetes
* In 1924 he discovered that compared to
the processes in the yeast cell glucose has
to be broken down to an ester product in
order to breakdown further
 In 1927 he discovered what is now named
as “Embdem ester” in the muscle cells
 By the time of his death (1933) him and his
assistant traced all the steps of conversion
of glycogen to lactic acid
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Embden noticed that results would be unsatisfactory if
experiment were conducted on both undissected and dissected
animals
Consequently he used a perfusion technique to conduct
experiments using the livers of warm blooded animals
The new perfusion method helped keep the dissected liver
intact
As a result he found out that oxidative deamination is a way to
break down the synthesis reaction of sugar to lactic acid
His results also showed that metabolism in liver is highly significant
His studies on carbohydrate metabolism led him to an interest in
chemical processes in muscular activity
His work led to the discovery of adenyl phosphoric acid in the
muscle that open a new large field in biochemistry
› http://dictionary.reference.com/browse/embden-
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