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Research has been conducted on the bile salt hydrolase (BSH). The results of isolation, purification and characterization of BSH from Bifidobacterium longum are discussed.

Research has been conducted on the Agrobacterium biovar gall isolates. The analysis of the plasmid-borne and chromosome-encoded traits of these isolates has been carried out.

The bifidobacterial response to bile salts is studied. The conjugated bile salt hydrolase (BSH) obtained from Bifidobacterium longum BB536 is purified, and during denaturing polyacrylamide gel electrophoresis its apparent molecular mass is ca. 40000 Da. The hexamer BSH from B. longum BB536 resides in the intracellular space. There is no considerable difference between the initial deconjugation rate and enzymatic efficiency in bile salts for B. longum.

The practical applicability and analytical performance of laserexcited Shpol' skii spectroscopy (LESS) for the determination of benzo[a]pyrene (BaP) metabolites was studied. Quantitation of these compounds in fish bile can provide insight into the BaP uptake from a contaminated aquatic environment (biomonitoring). Chemical derivatization of hydroxylated BaP metabolites with methyl iodide (to improve the compatibility with the Shpol' skii matrix) was tested. The methylation of phenolic metabolites was rapid and quantitative, but with BaP-dihydro diol metabolites, mixtures of methylation and elimination products were formed. An analytical procedure was developed for the quantitative determination of 3-OH-BaP, the major BaP metabolite detected in biie from flounder (Platichthys flesus). With LESS, the detection limit was 0.005 ng/mL (200 amol); the repeatability was 16%. The method was applied to a mesocosm experiment in which flounders were exposed to different sediments. The average BaP uptake from Rotterdam harbor sediment was 40 times higher than the uptake from Wadden Sea sand. Direct contact with the sediments was a major route of exposure. The usefulness of the method for the biomonitoring of polycyclic aromatic hydrocarbon stress in the aquatic environment is discussed., The characterization of benzo(a)pyrene (BaP) metabolites in fish bile by laser-excited Shpol'skii spectroscopy was studied. The phenoli and dihydro diol metabolites of BaP were quantified from a flatfish species flounder exposed to BaP by parental injection or mesocom systems with different sediments. The utility of the approach for polycyclic aromatic hydrocarbon stress analysis was demonstrated.

Variegate porphyria is an inherited disorder of porphyrin metabolism. Porphyrins are a class of organic chemical compounds which are important constituents of hemoglobin and a number of critical enzymes. Patients with variegate porphyria may have skin that is especially susceptible to mechanical damage, particularly areas exposed to light. Neurologic complications are also common among these patients. The diagnosis of variegate porphyria is not easy. Even during acute attacks of the symptoms, the urinary output of abnormal porphyrin metabolic products may resemble those from other sorts of porphyria disorders, particularly acute intermittent porphyria. While the porphyrin precursors produced in the feces may be more diagnostic, the porphyrin content of the feces is affected not only by the disease process, but also by the consumption of different sorts of foods and by variations in the bacteria which colonize the digestive tract. A study was thus undertaken to determine if direct sampling of the bile might provide better diagnostic capabilities than other methods. Bile is secreted by the liver and stored in the gallbladder until it is dumped into the duodenum of the small intestine during the digestive process. A sample of bile may be obtained by anesthetizing the patient's throat, then passing a tube down through the stomach into the duodenum. When an analysis was performed on the bile obtained in this manner, the lowest porphyrin amount of any patient with variegate porphyria was found to be nine time greater than the highest amount for any normal individual tested. The analysis of fecal samples from the same patients showed much smaller differences, and four of the 10 patients tested had amounts of porphyrin within normal range when tested in this way. The results of the study suggest that the analysis of bile may be more useful in the diagnosis of variegate porphyria than fecal samples. (Consumer Summary produced by Reliance Medical Information, Inc.)

The objective of this study was to examine whether ion pair complexation with endogenous bile salts in hepatocytes contributes to the preferential biliary excretion of organic cations (OCs). Tributylmethylammonium (TBuMA; mol wt 200) and triethylmethylammonium (TEMA; mol wt 116)were selected as model OCs that exhibit significant and negligible biliary excretion, respectively, in rats. The apparent lipophilicity of TBuMA, but not that of TEMA, was increased by the presence of either rat bile or specific bile salts, suggesting the formation of lipophilic ion pair complexes for TBuMA with bile salts in the liver. The uptake of TBuMA into canalicular liver plasma membrane (cLPM) vesicles, but not that of TEMA, was increased in the presence of bile salts, with a significant increase for both ATP-dependent transport and passive diffusion. The uptake of TBuMA in the presence of the bile salts was inhibited by representative P-glycoprotein (P-gp) substrates and vice versa, suggesting the involvement of P-gp in the canalicular excretion of TBuMA-bile salt complexes in vivo. Increased affinity toward P-gp is suggested as the mechanism responsible for the increased ATP-dependent transport for the ion pair complexes. We propose that ion pair formation with bile slats in hepatocytes may be responsible for the preferential biliary excretion of high-molecular-weight OCs including TBuMA. canalicular liver plasma membrane vesicles; P-glycoprotein; tributylmethylammonium; triethylmethylammonium

Gastric contents were sampled in horses via nasogastric tube to determine changes in pH and bile salt concentrations during feeding and fasting periods. The horses were rotated through 4 feeding [...]