We isolated three Sphingobium fuliginis strains from Phragmites australis rhizosphere sediment that were capable of utilizing 4-tert-butylphenol as a sole carbon and energy source. These strains are the first 4-tert-butylphenol-utilizing bacteria. The strain designated TIK-1 completely degraded 1.0 mM 4-tert-butylphenol in basal salts medium within 12 h, with concomitant cell growth. We identif...

The covalent flavoprotein vanillyl-alcohol oxidase (VAO) predominantly converts short-chain 4-alkylphenols, like 4-ethylphenol, to (R)-1-(4'-hydroxyphenyl)alcohols and medium-chain 4-alkylphenols, like 4-butylphenol, to 1-(4'-hydroxyphenyl)alkenes. Crystallographic studies have indicated that the active site residue Asp170 is involved in determining the efficiency of substrate hydroxylation. To...

Nonylphenol, a possible endocrine disrupter, tends to persist in rat liver tissue after detoxification as a glucuronide conjugate by UDP-glucuronosyltransferase 2B1 expressed in the liver. In the intestine, however, the metabolism and dynamics of nonylphenol remain to be elucidated. The objectives of this study were to clarify the metabolism and excretion of nonylphenol having a long alkyl chai...

BACKGROUND Alkylphenols, such as nonylphenol (NP) and 4-octylphenol (4-OP), have the potential to disturb immune system due to their weak estrogen-like activity, an effect with potential serious public health impact due to the worldwide distribution of these substances. Plasmacytoid dendritic cells (PDCs) can secrete large amounts of type I IFNs and are critical in immune regulation. However, t...

Nonylphenol, an environmental estrogenic chemical, is reported to have adverse effects on the reproductive organs of animals. In this study, the metabolism of nonylphenol and that of other alkylphenols in the rat liver was investigated using liver perfusion. Alkylphenols (nonylphenol, hexylphenol, butylphenol, and ethylphenol) were glucuronidated by rat liver microsomes. Nonylphenol was found t...

Enzymatic removal of p-alkylphenols from aqueous solutions was investigated through the two-step approach, the quinone conversion of p-alkylphenols with mushroom tyrosinase (EC 1.14.18.1) and the subsequent adsorption of quinone derivatives enzymatically generated on chitosan beads at pH 7.0 and 45 degrees C as the optimum conditions. This technique is quite effective for removal of various p-a...

The regio- and stereospecific conversion of prochiral 4-alkylphenols by the covalent flavoprotein vanillyl-alcohol oxidase was investigated. The enzyme was active, with 4-alkylphenols bearing aliphatic side chains of up to seven carbon atoms. Optimal catalytic efficiency occurred with 4-ethylphenol and 4-n-propylphenols. These short-chain 4-alkylphenols are stereoselectively hydroxylated to the...

Octyl- and nonylphenols in the environment have been proposed to function as estrogens. To gain insight into their structural essentials in binding to the estrogen receptor, a series of phenols with saturated alkyl groups at the para position, HO-C6H4-CnH2n+1 (n = 0-12), were examined for their ability to displace [3H]17beta-estradiol in the recombinant human estrogen receptor, which was expres...

The enzymes and genes responsible for the catabolism of higher alkylphenols have not been characterized in aerobic bacteria. Pseudomonas sp. strain KL28 can utilize a wide range of alkylphenols, which include the 4-n-alkylphenols (C(1)-C(5)). The genes, designated as lap (for long-chain alkylphenols), encoding enzymes for the catabolic pathway were cloned from chromosomal DNA and sequenced. The...

Alkylphenols and alkylphenol polyethoxylates are emerging hazardous contaminants due in particular to their endocrine-disrupting properties. These compounds originate from consumer products such as paints latex paints, adhesives, inks, formulation of pesticides, paper industry, textile leather petroleum recovery chemicals, metal working fluids, personal care products, washing agents, cleaners, ...