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The Entner–Doudoroff pathway (ED pathway) describes a pathway—a series of enzyme-catalyzed chemical reactions— that are active in bacterial primary metabolism, a pathway that catabolizes glucose to pyruvic acid using enzymes distinct either from those used in glycolysis or the pentose phosphate pathway (the latter two being most widely used in the Bacteria). The ED pathway was first reported by Michael Doudoroff and Nathan Entner from the Bacteriology Department at the University of California, Berkeley in 1952. Distinct features of the Entner–Doudoroff pathway are that it: * Occurs only in prokaryotes. * Uses 6-phosphogluconate dehydratase and 2-keto-3-deoxyphosphogluconate aldolase to create pyruvate from glucose. * Has a net yield of 1 ATP for every one glucose molecule processed, as well as 1 NADH and 1 NADPH. In comparison, glycolysis has a net yield of 2 ATP molecules and 2 NADH molecules for every one glucose molecule metabolised. ==Organisms that utilize the Entner-Doudoroff pathway== There are several bacteria that substitute the Entner–Doudoroff pathway for metabolism of glucose via glycolysis (e.g., therefore lacking essential glycolytic enzymes such as phosphofructokinase). Genera in which the pathway is prominent include Gram-negative, as listed below, Gram-positive bacteria such as Enterococcus faecalis, as well as several in the Archaea, the second distinct branch of the prokaryotes (and the "third domain of life", after the prokaryotic eubacteria and the eukaryotes).〔Bräsen C.; D. Esser; B. Rauch & B. Siebers (2014) "Carbohydrate metabolism in Archaea: current insights into unusual enzymes and pathways and their regulation," ''Microbiol. Mol. Biol. Rev.'' 78(1; March), pp. 89-175, DOI 10.1128/MMBR.00041-13, see () or (), accessed 3 August 2015.〕 Most organisms that use the pathway are aerobes, due to the low ATP yield per glucose molecule metabolised. Examples of bacteria using the pathway are: * ''Pseudomonas'',〔 a genus of Gram-negative bacteria * ''Azotobacter'', a genus of Gram-negative bacteria * ''Rhizobium'',〔Kuykendall, L. David; John M. Young; Esperanza Martínez-Romero; Allen Kerr & Hiroyuka Sawada (2006) ''Genus I.'' Rhizobium ''Frank 1889, 389AL'' (VI. Rhizobiales ''ord. nov.'', Family I Rhizobiaceae Conn 1938, 321AL (L. David Kuykendall, Ed.) ), pp. 324-339, in ''Bergey's Manual® of Systematic Bacteriology, ''Vol. 2'' The Proteobacteria, ''Part 3'' The Alpha-, Beta-, Delta-, and Epsilonproteobacteria,'' (Don J. Brenner, Noel R. Krieg, James T. Staley, Vol. Eds., George M. Garrity, Ed.-in-Chief), New York, NY, USA: Springer Science & Business, ISBN 0387241450, (), accessed 3 August 2015.〕 a plant root-associated and plant differentiation-active genus of Gram-negative bacteria * ''Agrobacterium'', a plant pathogen (oncogenic) genus of Gram-negative bacteria, also of biotechnologic use * ''Escherichia coli'', a Gram-negative bacterium * ''Enterococcus faecalis'', a Gram-positive bacterium * ''Zymomonas mobilis'', a Gram-negative ''facultative anaerobe * ''Xanthomonas campestris'', a Gram negative bacterium which uses this pathway as main pathway for providing energy. The Entner-Doudoroff pathway is present in many species of Archaea (caveat, see following), whose metabolisms "resemble... in () complexity those of Bacteria and lower Eukarya," and often include both this pathway and the Embden-Meyerhof-Parnas pathway of glycolysis, except most often as unique, modified variants.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Entner–Doudoroff pathway」の詳細全文を読む スポンサード リンク
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