The shikimate pathway is often referred to as the common aromatic biosynthetic pathway, even though nature does not synthesize a11 aromatic compounds by this route. This metabolic sequence converts the primary metabolites PEP and erythrose-4-P to chorismate, the last common precursor for the three aromatic amino acids Phe, Tyr, and Trp and for p-amino and p-hydroxy benzoate (Fig. 1). The shikim...

The halophile environment has a number of compelling aspects with regard to the origin of structured polypeptides (i.e., proteogenesis) and, instead of a curious niche that living systems adapted into, the halophile environment is emerging as a candidate "cradle" for proteogenesis. In this viewpoint, a subsequent halophile-to-mesophile transition was a key step in early evolution. Several lines...

I . The urinary excretions of total diethyl ether-soluble acids and total aromatic acids of three sheep given maintenance diets containing different proportions of hay, rolled oats and decorticated groundnut meal were determined. 2. When the sheep were given the diet containing 70 % rolled oats the excretion of aromatic acids in the urine was less than that observed when the sheep were given di...

IniB-the main external virulence factor of the bacterium Listeria monueytogenes- contains seven parallelB-strands at its concave face with a patches of five exposed aromatic amino acids as a hot spot for host receptor(Met) binding. For better understanding of energetic and physicochemical pmpendes, (u)folding transition,binding affinity and makmetic shielding censors of JAB-CRP-II-sheet ab hull...

Pseudomonas putida CSV86, a naphthalene-degrading organism, exhibited diauxic growth on aromatic compounds plus glucose, with utilization of aromatics in the first log phase and of glucose in the second log phase. Glucose supplementation did not suppress the activity of degrading enzymes, which were induced upon addition of aromatic compounds. The induction was inhibited by chloramphenicol, sug...

The unique aroma of melons (Cucumis melo L., Cucurbitaceae) is composed of many volatile compounds biosynthetically derived from fatty acids, carotenoids, amino acids, and terpenes. Although amino acids are known precursors of aroma compounds in the plant kingdom, the initial steps in the catabolism of amino acids into aroma volatiles have received little attention. Incubation of melon fruit cu...

The determination of aromatic acids by ion exclusion chromatography is challenging due to peak tailing and the long retention time of hydrophobic solutes. This review discusses the retention mechanisms and the factors affecting retention, eluents and detection methods used in ion exclusion chromatography of aromatic acids such as mono-, di-, tri- and tetra-carboxylic acids, amino acids, sulfona...

silica-bonded n-propyldiethylenetriamine sulfamic acid (sbpdsa) was found as an efficient solid acid for the synthesis of coumarins. coumarin derivatives were obtained via the pechmann condensation reaction of phenols and β-keto-esters at 80 oc under solvent-free conditions. also, biscoumarins were obtained via the condensation of aldehydes and 4-hydroxycoumarin in water at reflux conditions. t...