The proteasome inhibitor PS-341 markedly enhances sensitivity of multiple myeloma tumor cells to chemotherapeutic agents.

Increased nuclear factor kappaB (NF-kappaB) activity is associated with increased tumor cell survival in multiple myeloma. The function of NF-kappaB is inhibited through binding to its inhibitor, IkappaB. Release of activated NF-kappaB follows proteasome-mediated degradation of IkappaB resulting from phosphorylation of the inhibitor and, finally, conjugation with ubiquitin.

Comparative anatomy of the paratympanic organ (vitali organ) in the middle ear of birds and non-avian vertebrates: focus on alligators, parakeets and armadillos.

The paratympanic organ (PTO) in the middle ear has been described in numerous bird species, but little is known about the distribution of this presumed lateral line remnant in other vertebrate classes. Here we provide evidence for a PTO in juvenile alligators, and make the first detailed description of its location and relation to ligaments in the reptilian middle ear. The alligator PTO measures about 450 micro m in diameter.

Exploiting expolysaccharides from lactic acid bacteria.

Microbial exopolysaccharides (EPSs) synthesized by lactic acid bacteria (LAB) play a major role in the manufacturing of fermented dairy products. EPS production is characterized by a large variety in terms of quantity, chemical composition, molecular size, charge, type of sidechains and rigidity of the molecules. Monosaccharide unit's composition, linkages, charge and size determine the EPS' intrinsic properties and their interactions with other milk constituents.

Selection of dairy bacterial strains as probiotics for oral health.

The aim of the present study was to select bacterial strains with potential properties as oral probiotics, namely for the prevention of dental caries. We examined 23 dairy microorganisms, out of which we identified two Streptococcus thermophilus and two Lactcoccus lactis strains that were able to adhere to saliva-coated hydroxyapatite beads to the same extent as Streptococcus sobrinus OMZ176. Two of them, Strep.

Routine o-glycan characterization in nutritional supplements--a comparison of analytical methods for the monitoring of the bovine kappa-casein macropeptide glycosylation.

Analytical procedures, including capillary isoelectric focusing (CIEF), high-performance anion-exchange chromatography coupled to amperometric detection (HPAEC-PAD) and normal-phase chromatography with fluorescence detection are presented for the characterization of a highly O-glycosylated caseinomacropeptide (CGMP) and the detection of subtle glycosylation differences between CGMP Batches obtained with two different preparation procedures. Modified two-step CIEF allowed monitoring of glycopeptide heterogeneity and determination of the isoelectric points of acidic glycoforms. The mixture of wide and narrow pH range ampholytes was optimized to improve glycoform resolution.

Structure and properties of the exopolysaccharide produced by Streptococcus macedonicus Sc136.

Streptococcus macedonicus is a Gram positive lactic acid bacterium that is part of the starter flora present in Greek sheep and goat cheeses. The S. macedonicus Sc136 strain produces a high-molecular-mass, highly texturizing exopolysaccharide composed of D-glucose, D-galactose, and N-acetyl-D-glucosamine in the molar ratio of 3:2:1.

Glycosphingolipid binding specificities of rotavirus: identification of a sialic acid-binding epitope.

The glycosphingolipid binding specificities of neuraminidase-sensitive (simian SA11 and bovine NCDV) and neuraminidase-insensitive (bovine UK) rotavirus strains were investigated using the thin-layer chromatogram binding assay. Both triple-layered and double-layered viral particles of SA11, NCDV, and UK bound to nonacid glycosphingolipids, including gangliotetraosylceramide (GA1; also called asialo-GM1) and gangliotriaosylceramide (GA2; also called asialo-GM2). Binding to gangliosides was observed with triple-layered particles but not with double-layered particles.

Lactobacillus johnsonii La1 shares carbohydrate-binding specificities with several enteropathogenic bacteria.

The carbohydrate-binding specificities of the probiotic lactic acid bacterium Lactobacillus johnsonii La1 (a health-beneficial bacterial strain able to be incorporated into the human intestinal microflora) were investigated in vitro. First various soluble complex carbohydrates were tested as potential inhibitors of the strain adhesion onto Caco-2 intestinal epithelial cells, and then bacterial binding to glycolipids immobilized on TLC plates was probed. Two major carbohydrate-binding specificities of Lactobacillus johnsonii La1 were identified.

Bifidobacterium strains from resident infant human gastrointestinal microflora exert antimicrobial activity.

Background And Aims: The gastrointestinal microflora exerts a barrier effect against enteropathogens. The aim of this study was to examine if bifidobacteria, a major species of the human colonic microflora, participates in the barrier effect by developing antimicrobial activity against enterovirulent bacteria.

Methods: Antibacterial activity was examined in vitro against a wide range of Gram negative and Gram positive pathogens.

The development of functional foods: lessons from the gut.

Functional foods have resulted from the gradual recognition that healthy diets result from eating nutritious foods and from the identification of the mechanisms by which foods modulate metabolism and health. After initial successes with foods that reduce blood cholesterol level, probiotic bacteria and prebiotic carbohydrates have now also demonstrated added health benefits. As ingredients become more complex, the need to stabilize such ingredients in foods become increasingly important to the success of functional foods.

Powdered milk micellar casein prevents oral colonization by Streptococcus sobrinus and dental caries in rats: a basis for the caries-protective effect of dairy products.

Three animal studies were performed to investigate the influence of the macromolecular structure of milk casein on caries incidence and the possible ecological changes of the oral microbiota by such casein fractions. Towards this end, rats were infected with mixed bacterial suspensions of Streptococcus sobrinus OMZ 176 and Actinomyces viscosus Ny1. Various milk protein fractions were incorporated into carefully balanced powdered cariogenic diets to constitute the sole major protein component.

Unraveling the function of glycosyltransferases in Streptococcus thermophilus Sfi6.

Streptococcus thermophilus Sfi6 produces a texturizing exopolysaccharide (EPS) consisting of a -->3)[alpha-D-Galp-(1-->6)]-beta-D-Glcp-(1-->3)-alpha-D-GalpNAc-(1--> 3)-beta-D-Galp-(1--> repeating unit. We previously identified and analyzed a 14.5-kb gene cluster from S.

Introduction of the exopolysaccharide gene cluster from Streptococcus thermophilus Sfi6 into Lactococcus lactis MG1363: production and characterization of an altered polysaccharide.

Streptococcus thermophilus Sfi6 produces an exopolysaccharide (EPS) composed of glucose, galactose and N-acetylgalactosamine in the molar ratio of 1:2:1. The genes responsible for the EPS biosynthesis have been isolated previously and found to be clustered in a 14.5 kb region encoding 13 genes.

Development of a capillary zone electrophoresis method for caseinoglycomacropeptide determination.

Caseinoglycomacropeptide (CGMP) is a polypeptide of 64 amino acid residues, derived from the C-terminal part of bovine kappa-casein. A sensitive and selective capillary zone electrophoresis method has been developed and validated for the analysis and quantitation of CGMP. Separation is carried out at 30 kV, using an uncoated fused-silica capillary and 20 mM sodium citrate buffer at acidic pH 3.

Molecular organisation of the ice nucleation protein InaV from Pseudomonas syringae.

A new ice nucleation gene from Pseudomonas syringae was isolated and overexpressed as a fully active protein in Escherichia coli in order to gain experimental data about the structure of ice nucleation proteins. No evidence of a signal sequence or secondary glycosylation was found. Differences in the extent of aggregation were shown to modulate the ice nucleation activity.

Structural characterization of the exocellular polysaccharides produced by Streptococcus thermophilus SFi39 and SFi12.

We investigated the structures of the exopolysaccharides (EPSs) produced by Streptococcus thermophilus SFi39 and SFi12. Both polymers were found to have molecular masses of greater than 2 x 10(6) Da. The SFi39 EPS consisted of D-glucose and D-galactose in a molar ratio of 1:1, whereas the SFi12 EPS was composed of D-galactose, L-rhamnose, and D-glucose in a molar ratio of 3:2:1.

Lactobacillus helveticus Lh59 secretes an exopolysaccharide that is identical to the one produced by Lactobacillus helveticus TN-4, a presumed spontaneous mutant of Lactobacillus helveticus TY1--2.

Lactobacillus helveticus Lh59 produces a high-molecular-mass exopolysaccharide (> or = 2 x 10(6) Da) when cultured in skimmed milk. Compositional analysis, methylation analysis and NMR experiments (1H and 13C) recorded from the native polysaccharide as well as from oligosaccharides released by partial acid hydrolysis, allowed the complete structural determination of this polysaccharide, which consists of the following hexasaccharide repeating unit: [symbol: see text] This structure is identical to the one of an EPS produced by L. helveticus TN-4, which was claimed to be a spontaneous mutant of strain TY1-2.

The human Lactobacillus acidophilus strain LA1 secretes a nonbacteriocin antibacterial substance(s) active in vitro and in vivo.

The adhering human Lactobacillus acidophilus strain LA1 inhibits the cell association and cell invasion of enteropathogens in cultured human intestinal Caco-2 cells (M. F. Bernet, D.

Incorporation of caseinoglycomacropeptide and caseinophosphopeptide into the salivary pellicle inhibits adherence of mutans streptococci.

The protective effects of milk and milk products against dental caries have been demonstrated in many animal studies. We have shown that this effect was mediated by micellar casein or caseinopeptide derivatives. A reduction in the Streptococcus sobrinus population in the oral microbiota of animals fed diets supplemented with these milk components was consistently observed.

Identification and characterization of the eps (Exopolysaccharide) gene cluster from Streptococcus thermophilus Sfi6.

We report the identification and characterization of the eps gene cluster of Streptococcus thermophilus Sfi6 required for exopolysaccharide (EPS) synthesis. This report is the first genetic work concerning EPS production in a food microorganism. The EPS secreted by this strain consists of the following tetrasaccharide repeating unit:-->3)-beta-D-Galp-(1-->3)-[alpha-D-Galp-(1-->6)]-beta-D- D-Galp-(1-->3)-alpha-D-Galp-D-GalpNAc-(1-->.

Binding of the fibrillar CS3 adhesin of enterotoxigenic Escherichia coli to rabbit intestinal glycoproteins is competitively prevented by GalNAc beta 1-4Gal-containing glycoconjugates.

We have attempted to characterize the binding specificity of the coli surface 3 (CS3) subcomponent of colonization factor antigen II of enterotoxigenic Escherichia coli, by means of an immunoblot method in which the binding of fimbriated bacteria to sodium dodecyl sulfate-polyacrylamide gel electrophoresis-separated rabbit intestinal cell membranes was evaluated. Isolated CS3 fibrillae as well as bacteria expressing CS3 on their surface bound to several intestinal cell membrane structures, i.e.

A 23 kDa membrane glycoprotein bearing NeuNAc alpha 2-3Gal beta 1-3GalNAc O-linked carbohydrate chains acts as a receptor for Streptococcus sanguis OMZ 9 on human buccal epithelial cells.

Streptococcus sanguis colonizes several human oral surfaces, including both hard and soft tissues. Large salivary mucin-like glycoproteins bearing sialic acid residues are known to bind various S.sanguis strains.

In vitro modulation of oral bacterial adhesion to saliva-coated hydroxyapatite beads by milk casein derivatives.

Bovine caseinate, derivatives of its glycosylated moiety [caseinoglycomacropeptide (CGP)], and caseinophosphopeptides were evaluated as inhibitors of adhesion of oral bacteria to saliva-coated hydroxyapatite beads (S-HA). All milk casein-derived components behaved as potent inhibitors of Streptococcus sanguis OMZ 9 and Streptococcus sobrinus OMZ 176 adhesion to S-HA, whereas neither bovine serum albumin nor polyethyleneglycol were able to interfere with the adhesion of these strains. By contrast, none of the molecular species tested was able to inhibit the attachment of Actinomyces viscosus Ny 1 to S-HA.

Lactobacillus acidophilus LA 1 binds to cultured human intestinal cell lines and inhibits cell attachment and cell invasion by enterovirulent bacteria.

Four human Lactobacillus acidophilus strains were tested for their ability to adhere onto human enterocyte like Caco-2 cells in culture. The LA 1 strain exhibited a high calcium independent adhesive property. This adhesion onto Caco-2 cells required a proteinaceous adhesion promoting factor, which was present in the spent bacterial broth culture supernatant.