ABSTRACT
The effects of multiwalled carbon nanotubes on epitheliocytes of different compartments of the gastrointestinal tract and urothelium of different compartments of the renal nephron were studied in CBA mice. The nanotubes affected mouse gastrointestinal mucosa and renal urothelium. The cell reaction in the macula densa of the renal distal tubules and the immune system reaction to oral nanotubes were detected. A possible effect of nanotubes administered orally on the renal filtration function was hypothesized.
Subject(s)
Drug Carriers/toxicity , Intestinal Mucosa/drug effects , Nanotubes, Carbon/toxicity , Administration, Oral , Animals , Drug Carriers/metabolism , Gastrointestinal Tract/cytology , Gastrointestinal Tract/drug effects , Intestinal Absorption , Kidney Tubules, Distal/drug effects , Male , Mice , Mice, Inbred CBA , Urothelium/drug effectsABSTRACT
A possibility of adhesion inhibition of Corynebacterium diphtheriae to human buccal epithelium by glycoside hydrolases of marine hydrobiontes was investigated using alpha-galactosidase from marine bacterium Pseudoalteromonas sp. KMM 701, total enzyme preparation and beta-1,3-glucanase from marine fungi Chaetomium, total enzyme preparation and beta-1,3-glucanase from marine mollusk Littorina kurila, and total enzyme preparation from crystalline style of marine mollusk Spisula sachalinensis were used. The enzymes were added to test-tubes containing buccal epithelial cells and/or the toxigenic bacterial strain C. diphtheriae No 1129, v. gravis. All the investigated enzymes were able to abort C. diphtheriae adherence, to human buccal epithelocytes. Inhibition of adhesion was more pronounced in the case of treatment of epithelocytes with highly purified enzymes of marine hydrobiontes in comparison with total enzyme preparations. The significant inhibition of C. diphtheriae adhesion was observed when the enzymes were added to the epithelocytes with the attached microorganisms. The results obtained show that glycoside hydrolases of marine hydrobiontes degrade any carbohydrates expressed on cell surface of bacterium or human buccal epithelocytes, impair unique lectin-carbohydrate interaction and prevent the adhesion.
Subject(s)
Bacterial Adhesion , Corynebacterium diphtheriae/physiology , Glycoside Hydrolases/pharmacology , Mouth Mucosa/drug effects , Animals , Chaetomium/enzymology , Crustacea/enzymology , Epithelial Cells/drug effects , Epithelial Cells/microbiology , Glucan 1,3-beta-Glucosidase/isolation & purification , Glucan 1,3-beta-Glucosidase/pharmacology , Glycoside Hydrolases/isolation & purification , Humans , In Vitro Techniques , Mouth Mucosa/microbiology , Pseudoalteromonas/enzymology , Spisula/enzymology , alpha-Galactosidase/isolation & purification , alpha-Galactosidase/pharmacologyABSTRACT
A beta-1,3-glucanase with a molecular mass of 33 kDa was isolated in the homogeneous state from a crystalline stalk of the commercially available Vietnamese edible mussel Perna viridis. It hydrolyzes beta-1,3-bonds in glucans and is capable of catalyzing the transglycosylation reaction. The beta-1,3-glucanase has a K(m) value of 0.3 mg/ml for the hydrolysis of laminaran and shows a maximum activity in the pH range from 4 to 6.5 and at 45 degrees C. Its half-inactivation time is 180 min at 45 degrees C and 20 min at 50 degrees C. The enzyme was ascribed to glucan-endo-(1-3)-beta-D-glucosidases (EC 3.2.1.39). The enzyme could be used in the structure determination of beta-1,3-glucans and enzymatic synthesis of new carbohydrate-containing compounds.
Subject(s)
Glucan 1,3-beta-Glucosidase/chemistry , Glucans/metabolism , Mytilidae/enzymology , Animals , Catalysis , Glucan 1,3-beta-Glucosidase/isolation & purification , Glucan 1,3-beta-Glucosidase/metabolism , Hydrogen-Ion Concentration , Hydrolysis , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Substrate Specificity , VietnamABSTRACT
An aryl sulfatase of unusual specificity has been isolated from the liver of marine mollusk Littorina kurila. It hydrolyzes p-nitrophenyl sulfate, does not affect the natural fucoidan, and catalyzes splitting off of the sulfate group in position C4 of xylose residues within the carbohydrate chains of holostane triterpene glycosides from sea cucumbers. The properties of the enzyme were studied at pH 5.4. The protein is homogeneous according to electrophoresis and has M 45 +/- 1 kDa. The semiinactivation time of the enzyme at 60 degrees C is 20 min, and its Km value for the hydrolysis of p-nitrophenyl sulfate is 8.7 +/- 1 mM. It was shown that natural sulfated polyhydroxysteroids inhibit activity of the sulfatase; their I50 values depend on their structures and are within the range from 10(-3) to 10(-5) M.
Subject(s)
Arylsulfonates/metabolism , Liver/enzymology , Snails/enzymology , Animals , Arylsulfonates/antagonists & inhibitors , Arylsulfonates/chemistry , Dose-Response Relationship, Drug , Enzyme Inhibitors/pharmacology , Glycosides/chemistry , Glycosides/metabolism , Liver/chemistry , Polysaccharides/chemistry , Polysaccharides/metabolism , Snails/chemistry , Steroids/pharmacology , Substrate Specificity/drug effects , Triterpenes/chemistry , Triterpenes/metabolismABSTRACT
Polysaccharide composition of neutral, acid- and alkali-soluble fractions of the diatoms Stephanodiscus meyerii Genkal et Popovsk and Aulacoseira baicalensis (K. Meyer) Simonsen of Lake Baikal has been studied. Neutral polysaccharides were represented by chrysolaminarans (1-->3;1-->6-beta-D-glucans). The chrysolaminaran from S. meyerii consists of the high- and low-molecular-weight fractions (40 and 2-5 kDa, respectively) and contains a large number of beta-1-->6-bound glucose residues. The chrysolaminaran from A. baicalensis is a low-molecular-weight 1-->3:1-->6-beta-D-glucan containing a small number of beta-1-->6 bonds, with mannitol being attached to the reducing unit of its chain. Acid- and alkali-soluble polysaccharide fractions are practically absent in S. meyerii. The alkali-soluble fraction from A. baicalensis is a low-molecular-weight (2-kDa) glycoprotein, the carbohydrate moiety of which is represented by a heteropolysaccharide.
