1420-36-6Relevant articles and documents
Thiamine pyrophosphate stimulates acetone activation by desulfococcus biacutus as monitored by a fluorogenic ATP analogue
Gutiérrez Acosta, Olga B.,Hardt, Norman,Hacker, Stephan M.,Strittmatter, Tobias,Schink, Bernhard,Marx, Andreas
, p. 1263 - 1266 (2014)
Acetone can be degraded by aerobic and anaerobic microorganisms. Studies with the strictly anaerobic sulfate-reducing bacterium Desulfococcus biacutus indicate that acetone degradation by these bacteria starts with an ATP-dependent carbonylation reaction leading to acetoacetaldehyde as the first reaction product. The reaction represents the second example of a carbonylation reaction in the biochemistry of strictly anaerobic bacteria, but the exact mechanism and dependence on cofactors are still unclear. Here, we use a novel fluorogenic ATP analogue to investigate its mechanism. We find that thiamine pyrophosphate is a cofactor of this ATP-dependent reaction. The products of ATP cleavage are AMP and pyrophosphate, providing first insights into the reaction mechanism by indicating that the reaction proceeds without intermediate formation of acetone enol phosphate.
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Lynen,Ochoa
, p. 299,310 (1953)
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Characterization of a highly thermostable ss-hydroxybutyryl CoA dehydrogenase from Clostridium acetobutylicum ATCC 824
Sommer, Bettina,Garbe, Daniel,Schrepfer, Patrick,Brueck, Thomas
, p. 138 - 144 (2013)
Higher energy content and hydrophobicity make bio-based n-butanol a preferred building block for chemical and biofuels manufacturing. Butanol is obtained by Clostridium sp. based ABE fermentation process. While the ABE process is well understood, the enzyme systems involved have not been elucidated in detail. The important enzyme ss-hydroxybutyryl CoA dehydrogenase from Clostridium acetobutylicum ATCC 824 (Hbd) was purified and characterized. Surprisingly, Hbd shows extremely high temperature (T > 60 C), pH (4-11) and solvent (1-butanol, isobutanol, ethanol) stability. Hbd catalyzes acetoacetyl CoA hydration to ss-hydroxybutyryl CoA up to pH 9.5, where the reaction is reversed. Substrate (acacCoA, ss-hbCoA) and cofactor (NADH, NAD +, NADPH and NADP+) specificities were determined. We identified NAD+ as an uncompetitive inhibitor. Identification of process relevant enzymes such as Hbd is key to optimize butanol production via cellular or cell-free enzymatic systems.