Aromatic biosynthesis: XVI. Aromatization of prephenic acid (cas 126-49-8) to p-hydroxyphenylpyruvic acid, a step in tyrosine biosynthesis in Escherichia coli☆

Add time:09/25/2019    Source:sciencedirect.com

Prephenic dehydrogenase, a soluble enzyme from E. coli, catalyzes an aromatization reaction which converts prephenic acid (cas 126-49-8) (PPA) to p-hydroxyphenylpyruvic acid (HPP) with DPN as the oxidant. The absence of this reaction in tyrosine auxotrophs indicates that it is an obligatory step in tyrosine biosynthesis; furthermore, it is distinct from the aromatization reaction leading to phenylalanine. Partly purified prephenic dehydrogenase incubated with PPA under certain conditions yields p-hydroxyphenylpyruvic acid as the only phenolic product; with proper fortification this product is converted quantitatively to tyrosine. Under incubation conditions favoring DPNH stability, some p-hydroxyphenyllactic acid (HPL) is also formed, but this compound is a secondary product and not an intermediate in tyrosine formation. Prephenic dehydrogenase is rather unstable but is stabilized by the presence of PPA. The level of the enzyme in E. coli extracts is markedly altered by changes in thebacterial growth medium.

We also recommend Trading Suppliers and Manufacturers of prephenic acid (cas 126-49-8). Pls Click Website Link as below: cas 126-49-8 suppliers

Prev:Regular ArticleA thermodynamic investigation of some reactions involving prephenic acid (cas 126-49-8)
Next:Syringic acid (SA) ‒ A Review of Its Occurrence, Biosynthesis, Pharmacological and Industrial Importance)