Zymase

Zymase

Zymase is an enzyme complex ("mixture") that catalyzes glycolysis, the fermentation of sugar into ethanol and carbon dioxide. As the conversion takes place, the reaction will gradually slow down. They occur naturally in yeasts. See alcohol dehydrogenase.

Zymase was first isolated from the yeast cell in 1897 by a German chemist named Eduard Buchner who fermented sugar in the laboratory without living cells, leading to 1907 Nobel Prize in Chemistry.

Cell-free fermentation experiment

The experiment for which Buchner won the Nobel Prize consisted of producing a cell-free extract of yeast cells and showing that this "press juice" could ferment sugar. This dealt yet another blow to vitalism by showing that the presence of living yeast cells was not needed for fermentation. The cell-free extract was produced by combining dry yeast cells, quartz and kieselguhr and then pulverizing the yeast cells with a mortar and pestle. This mixture would then become moist as the yeast cells' contents would come out of the cells. Once this step was done, the moist mixture would be put through a press and when this resulting "press juice" had glucose, fructose, or maltose added, carbon dioxide was seen to evolve, sometimes for days. Microscopic investigation revealed no living yeast cells in the extract.

One interesting thing is that Buchner hypothesized that yeast cells secrete proteins into their environment in order to ferment sugars, instead of the fermentation occurring inside the yeast cells, which is the actual mechanism.

British chemist Sir Arthur Harden divided zymase into two varieties (dialyzable and nondialyzable) in 1905.

Zymase is also the brand name of the generic enzyme mixture pancrelipase, a dietary supplement containing the enzymes amylase, peptidase, and lipase. It is sold to help digestion in people who do not produce enough of their own digestive enzymes.


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  • zymase — [ zimaz ] n. f. • 1864; de zym(o) et ase ♦ Biochim. vx ⇒ enzyme. Mod. spécialt Enzyme qui détermine la fermentation alcoolique du glucose. ● zymase nom féminin Synonyme ancien de enzyme. ● zymase (synonymes) nom féminin Synonymes …   Encyclopédie Universelle

  • Zymase — ist ein Enzym, das aus Hefe gewonnen wird. Es katalysiert die alkoholische Gärung von Hexosen. Zymase ist auch die Sammelbezeichnung für die zur Gärung in der Hefe notwendigen Enzyme. Letztere führten Eduard Buchner zur Entdeckung der zellfreien… …   Deutsch Wikipedia

  • Zymase — ym ase, n. [From {Zyme}.] (Physiol. Chem.) A soluble ferment, or enzyme. See {Enzyme}. [1913 Webster] …   The Collaborative International Dictionary of English

  • Zymase — Zymase, s. Gärung, S. 360, und Hefe, S. 48 …   Meyers Großes Konversations-Lexikon

  • Zymase — Zymāse (grch.), die aus zerriebener Hefe gepreßte Substanz, ein Enzym, das die alkoholische Gärung des Zuckers bewirkt …   Kleines Konversations-Lexikon

  • Zymase — est le nom donné par Antoine Béchamp aux « ferments solubles », tels que l’amylase, la pepsine, etc. qu il avait découvert. Sources Dictionnaire universel des sciences, des lettres et des arts, par Marie Nicolas Bouillet, 1896 Antoine… …   Wikipédia en Français

  • zymase — [zī′mās΄] n. [Fr: see ZYME + ASE] an enzyme, present in yeast, that promotes fermentation by breaking down glucose and some other carbohydrates into alcohol and carbon dioxide …   English World dictionary

  • zymase — (zi ma z ) s. f. Terme de chimie. Substance qui, dans les moisissures, est le ferment glycosique du sucre de canne, comme la diastase dans l orge germée est le ferment glycosique de la fécule. •   Une zymase est toujours le produit de l activité… …   Dictionnaire de la Langue Française d'Émile Littré

  • Zymase — Zy|ma|se 〈f. 19; unz.〉 Enzymgemisch aus Hefe, das Hexosen zu Alkohol vergären kann [zu grch. zyme „Sauerteig, Gärungsstoff“] * * * Zy|ma|se [↑ Zymo u. ↑ ase], die; : historische Bez. für das Enzymgemisch aus Hefeextrakten, das für die… …   Universal-Lexikon

  • Zymase — Zy|ma|se die; <aus gleichbed. fr. zymase, dies zu gr. zýmē, vgl. ↑zymo... u. ...ase> aus zellfreien Hefepresssäften gewonnenes Gemisch von ↑Enzymen, das die alkoholische Gärung verursacht …   Das große Fremdwörterbuch

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