p-Hydroxybenzoate hydroxylase, the product of the pobA gene, gives rise to protocatechuate, which is metabolized by enzymes encoded by the pca operon in Acinetobacter calcoaceticus. Mutations in pcaD prevented growth of A. calcoaceticus with succinate in the presence of p-hydroxybenzoate. Mutants selected on this medium contained the original mutation in pcaD and also carried spontaneous mutati...

The crystal structure of the title compound, [Co(C(7)H(5)O(3))(C(12)H(8)N(2))(2)(H(2)O)](C(7)H(5)O(3))·5H(2)O, consists of Co(II) complex cations, uncoordinated hydroxy-benzoate anions and uncoord-inated water mol-ecules. The Co(II) ion is coordinated by two phenanthroline ligands, a water mol-ecule and a 3-hydroxy-benzoate anion, and displays a distorted octa-hedral geometry. π-π stacking is o...

An aldolase, which is induced in Pseudomonas testosteroni during growth with p-hydroxybenzoate, preferentially attacks the R form of 4-hydroxy-4-methyl-2-oxoglutarate, a metabolite of protocatechuate catabolism.

INTERMEDIATES IN FLAVOPROTEIN CATALYZED HYDROXYLATIONS Barrie Entsch, Vincent Massey and David P. Ballou Department of Biological Chemistry, The University of Michigan Ann Arbor, Michigan 48104 Received November 21,1973 Summary The reaction of molecular oxygen with the complex of reduced p-hydroxybenzoate hydroxylase and 2,4-dihydroxybenzoate has been followed by rapid reaction techniques. Duri...

In this paper, the electrochemical behaviour of several parabens preservatives, i.e. esters of p-hydroxybenzoic acid, methyl-, ethyl- and propyl-4-hydroxybenzoates as methyl-, ethyl- and propyl-parabens (MB, EB, and PB), has been investigated at a commercial boron-doped diamond electrode (BDDE), especially in the anodic potential range, in both hydro-alcoholic and aqueous media. The cyclic volt...

(a) bactericidal and fungicidal, (b) compatible with most chemicals used in ophthalmic preparations, (c) non-irritating and non-sensitizing. The most commonly accepted preservative is the mixture of methyl and propylhydroxybenzoates used in the " Solution for Eye-Drops" of the British Pharmaceutical Codex. These hydroxybenzoates, being relatively efficient fungicides, will keep the solutions fr...

Clostridium hydroxybenzoicum JW/Z-1T (= ATCC 51151 = DSM 7310)) (T = type strain), isolated from freshwater pond sediment, is a nonmotile, gram type-positive, spore-forming, amino acid-utilizing, anaerobic rod. This bacterium produces two inducible enzymes that catalyze the decarboxylation of para-hydroxybenzoates. The phenols produced are not utilized. C. hydroxybenzoicum requires yeast extrac...

The pathogenic yeast Candida parapsilosis metabolizes hydroxyderivatives of benzene and benzoic acid to compounds channeled into central metabolism, including the mitochondrially localized tricarboxylic acid cycle, via the 3-oxoadipate and gentisate pathways. The orchestration of both catabolic pathways with mitochondrial metabolism as well as their evolutionary origin is not fully understood. ...

Lignin acylation, the decoration of hydroxyls on lignin structural units with acyl groups, is common in many plant species. Monocot lignins are decorated with p-coumarates by the polymerization of monolignol p-coumarate conjugates. The acyltransferase involved in the formation of these conjugates has been identified in a number of model monocot species, but the effect of monolignol p-coumarate ...

Polyphenols, antioxidant potential and color of three types of fortified Madeira wines were evaluated during the accelerated ageing, named as estufagem. The traditional estufagem process was set to 45 °C for 3 months. Overheating conditions, 1 month at 70 °C, were also examined. Total polyphenols (TP), total monomeric anthocyanins (TMA) and total flavonoids (TF) were assessed by spectrophotomet...