A novel flavoprotein monooxygenase, 4-hydroxybenzoate 1-hydroxylase (decarboxylating), from Candida parapsilosis CBS604 was purified to apparent homogeneity. The enzyme is induced when the yeast is grown on either 4-hydroxybenzoate, 2,4-dihydroxybenzoate, or 3,4-dihydroxybenzoate as the sole carbon source. The purified monooxygenase is a monomer of about 50 kDa containing flavin adenine dinucle...

Poplar (Populus tremula x alba) lignins with exceedingly high syringyl monomer levels are produced by overexpression of the ferulate 5-hydroxylase (F5H) gene driven by a cinnamate 4-hydroxylase (C4H) promoter. Compositional data derived from both standard degradative methods and NMR analyses of the entire lignin component (as well as isolated lignin fraction) indicated that the C4HF5H transgeni...

This paper describes the novel preparation of three kinds of nanofibers [poly(styrene-co-methacrylic acid), poly(styrene-co-p-styrene sulfonate), polystyrene] investigated as solid-phase extraction (SPE) sorbents to extract six compounds (nitrobenzene, 2-naphthol, benzene, n-butyl p-hydroxybenzoate, naphthalene, p-dichlorobenzene) in environmental water by high-performance liquid chromatography...

Significant selective enrichments of mutants defective in catabolic pathways can be achieved by exposure of pseudomonad cells to halogenated analogs of growth substrates. Between 3 and 95% of viable clones rescued from such enrichments have been defective in specific catabolic pathways. This has been demonstrated for eight different catabolic pathways for aromatic compounds in pseudomonads, in ...

Pseudomonas sp. strain JS6 grows on chlorobenzene, p-dichlorobenzene, or toluene as a sole source of carbon and energy. It does not grow on p-chlorotoluene (p-CT). Growth on glucose in the presence of p-CT resulted in the accumulation of 4-chloro-2,3-dihydroxy-1-methylbenzene (3-chloro-6-methylcatechol), 4-chloro-2,3-dihydroxy-1-methylcyclohexa-4,6-diene (p-CT dihydrodiol), and 2-methyl-4-carbo...

1. Dihydroxyfumarate slowly autoxidizes at pH6. This reaction is inhibited by superoxide dismutase but not by EDTA. Mn2+ catalyses dihydroxyfumarate oxidation by reacting with O2 leads to to form Mn3+, which seems to oxidize dihydrofumarate rapidly. Cu2+ also catalyses dihydroxyfumarate oxidation, but by a mechanism that does not involve O2 leads to. 2. Peroxidase catalyses oxidation of dihydro...

An enzyme that converts p-hydroxycinnamate into p-hydroxybenzoate was found in rat liver. It is localized in the mitochondria and requires ATP. The activity is lost when the mitochondria are stored frozen overnight. Addition of magnesium chloride, cytochrome c, GSH, coenzyme A or potassium cyanide did not have any effect on the activity. When the rats were fed with alpha-p-chlorophenoxyisobutyr...

We describe a manual method, well suited to mechanization, for quantitating serum uric acid at 500 nm. In the assay mixture (0.10 ml of sample and 3.00 ml of reagent) the hydrogen peroxide produced from uric acid by uricase is coupled with p-hydroxybenzoate and 4-aminoantipyrine in the presence of peroxidase to form a colored complex, which is measured. A separate sample blank is obviated by ta...

Phenolic compounds biodegradation and its effect on the nitrification process were studied. A continuous stirrer tank reactor was operated in four stages, and phenolic compounds were fed as sequential way. In the first stage, at loading rate of 220 mg NH(4)(+)-N/Ld, the consumption efficiency was of 91%, being the product, nitrate. After that, p-cresol was fed at 53 mg C/Ld, reaching removal ef...