Pyruvic acid

• 2 pyruvic acid
• 2-oxo- propionic acid
• α - Ketopropionsäure
• Pyruvate

Of acetic acid -smelling, colorless liquid

Liquid

1.27 g · cm -3

12 ° C

Decomposition at 165 ° C

2.49

Miscible with water

1.4280 (20 ° C)

Risk

3533 mg · kg -1 ( LD50, mouse, s.c )

Template: Infobox chemical / molecular formula search available

Pyruvic acid, also Acetylameisensäure, the simplest ketocarboxylic acids, their salts and esters are referred to as pyruvate. In biochemistry pyruvate denotes the anion of pyruvic acid. The molecule of pyruvic acid has a constant α - carbonyl group. The acyl radical ( CH3COCO ) of pyruvic acid is called " pyruvoyl ".

Representation

The term pyruvic acid is derived from the first production: tartaric acid was obtained by dry distillation subject (then known as Pyrolysis ); this creates pyruvic acid by decarboxylation and elimination of water. In English, the link is therefore called " Pyruvic acid", derived from the Greek " pyr " ( fire, heat ) and the Latin word " uva " ( grape, especially grapes ).

Jöns Jakob Berzelius has shown pyruvic acid in 1835 by co- Pyrolysis of tartaric acid with potassium hydrogen sulfate.

Properties

The flash point of the colorless, any water miscible liquid is 82 ° C.

Biochemical importance

The anion of pyruvic acid, pyruvate, represents an important intermediate in the aerobic and anaerobic metabolism

It arises, for example in the cytoplasm of a cell, when glucose is doubly phosphorylated and degraded in the glycolysis.

The reduction runs on the intermediates CAP and phosphoenolpyruvate.

Here, the cell per mole of glucose wins next 2 moles of pyruvic acid nor 2 mol ATP and 2 mol of NADH H . Pyruvate is an energy-rich compound, and may in the citric acid cycle ( TCA cycle also, citric acid cycle, tricarboxylic acid cycle or Krebs cycle called ) further reduced. From the obtained in glycolysis ( a mole of glucose ), 2 moles of pyruvate generated in the mitochondria of the cell case 6 moles of CO2, 8 moles of NADH H , 2 moles and 2 moles of ATP FADH2. By transamination of pyruvate ( L-glutamic acid reactant ) is formed of L-alanine (Ala ) (see picture A). Thus, the connection to the metabolism of amino acids (see glucose -alanine cycle, a variant of the well-known Cori cycle). At the same time setting the course between the occurrence of the pyruvate for gluconeogenesis (B) or the entry into the TCA cycle via the pyruvate dehydrogenase multienzyme complex ( power shortage situation, formation of acetyl -CoA) (C ) takes place at pyruvate but under anaerobic conditions, it can also are metabolized to lactic acid or ethanol (see fermentation).

During anaerobic fermentation formic acid bacteria metabolize pyruvate using the Formiatacetyltransferase to formic acid (D). In the first step of the alcoholic fermentation, pyruvate is reduced in plants, fungi and some bacteria using the pyruvate to acetaldehyde (E). Pyruvate, with the aid of lactate dehydrogenase (LDH) react to lactate, which can be further used in the anabolic and catabolic metabolism.

The metabolite pyruvic acid is concentrated at cell damage, for example, toxic, hypoxic or hypovitaminotischer kind in serum and urine; equally there is a Glykogenverarmung in the liver and muscles.

Proof

Of analytical detection may be carried out with phenyl, α - or β -naphthol or 2,4- dinitrophenyl.