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Type Culture Collection (type + culture_collection)
Kinds of Type Culture Collection Selected AbstractsBifidobacterium animalis causes extensive duodenitis and mild colonic inflammation in monoassociated interleukin-10-deficient miceINFLAMMATORY BOWEL DISEASES, Issue 7 2009James P. Moran PhD Abstract Background: We recently showed that Bifidobacterium animalis is more prevalent within the colons of interleukin (IL)-10-deficient (,/,) mice than in wildtype (WT) animals colonized with the same specific pathogen-free (SPF) fecal contents. Here we tested the ability of this organism to cause T-cell-mediated intestinal inflammation by introducing it into germ-free (GF) IL-10,/, mice. Methods: GF IL-10,/, or WT mice were monoassociated with Bifidobacterium animalis subsp. animalis ATCC (American Type Culture Collection, Manassas, VA) 25527T or with B. infantis ATCC 15697T. Inflammation was measured by blinded histologic scores of the duodenum, cecum, and colon and by spontaneous secretion of IL-12/IL-23 p40 from colonic explants. Bacterial antigen-specific CD4+ mesenteric lymph node (MLN) T-cell recall responses were measured in response to antigen-presenting cells (APC) pulsed with bacterial lysates. Results:B. animalis caused marked duodenal inflammation and mild colitis in monoassociated IL-10,/, mice, whereas the intestinal tracts of WT animals remained free of inflammation. B. infantis colonization resulted in mild inflammation in the duodena of IL-10,/, mice. CD4+ MLN T cells from B. animalis monoassociated IL-10,/, mice secreted high levels of IFN-, and IL-17 in response to B. animalis lysate. B. animalis equally colonized the different intestinal regions of WT and IL-10,/, mice. Conclusions:B. animalis, a traditional probiotic species that is expanded in experimental colitis in this model, induces marked duodenal and mild colonic inflammation and TH1/TH17 immune responses when introduced alone into GF IL-10,/, mice. This suggests a potential pathogenic role for this commensal bacterial species in a susceptible host. (Inflamm Bowel Dis 2009) [source] FREE RADICAL-SCAVENGING ACTIVITIES OF LOW MOLECULAR WEIGHT CHITIN OLIGOSACCHARIDES LEAD TO ANTIOXIDANT EFFECT IN LIVE CELLSJOURNAL OF FOOD BIOCHEMISTRY, Issue 2010DAI-NGHIEP NGO ABSTRACT Chitin oligosaccharides (NA-COS) with low molecular weight distribution of 229.21,593.12 Da were produced from crab chitin by acid hydrolysis. They showed reducing power and scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH) (Sigma Chemical Co., St. Louis, MO), hydroxyl and alkyl radicals. It was observed that the radical-scavenging activity of NA-COS increased in a dose-dependent manner. Their IC50 values for DPPH, hydroxyl and alkyl radicals were 0.8, 1.75 and 1.14 mg/mL, respectively. Furthermore, NA-COS exhibited the inhibitory effect on the oxidative damage of DNA from human lymphoma U937 (American Type Culture Collection, Manassas, VA) and the direct radical-scavenging effect in human fibrosarcoma cells (HT1080) (American Type Culture Collection) in 2,,7,-dichlorofluorescin diacetate (DCFH-DA) assay (Molecular Probes Inc., Eugene, OR). The results suggest that NA-COS can exert antioxidant effect in live cells and have the potential to be applied to food supplements or nutraceuticals. PRACTICAL APPLICATIONS Chitin oligosaccharides (NA-COS) are the hydrolyzed products of chitin (KEUMHO chemical products Co. Ltd., Gyeongbuk, Korea) of which derivatives have shown antioxidant, antimicrobial, anticancer, anti-inflammatory and immunostimulant effects. According to previous studies, NA-COS have beneficial biological activities similar to those of chitin. Furthermore, they are easily soluble in water because of their shorter chain length. Therefore, NA-COS are potentially applicable to improve food quality and human health. [source] THERMAL DEATH TIMES OF ESCHERICHIA COLI IN YOUNG COCONUT ENDOSPERM BEVERAGEJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 2009ALONZO A. GABRIEL ABSTRACT The decimal reduction times (D values) of Escherichia coli (American Type Culture Collection 25922) were established in a young coconut endosperm beverage, a famous local drink in the Philippines and in many tropical countries. Artificially inoculated cells were heated to 60, 70 and 80C at various heating times prior to survivor enumeration by surface plating onto pre-solidified Eosine Methylene Blue Agar. Results showed that the surviving populations significantly (P < 0.05) decreased with increasing exposure time and temperature. The calculated D values ranged from 0.26 ± 0.01 to 0.56 ± 0.08 min. Validation of the results by establishing the thermal resistance of other E. coli isolates in the coconut beverage medium was recommended. PRACTICAL APPLICATION The study established the thermal inactivation rates of Escherichia coli (American Type Culture Collection 25922) in a young coconut endosperm beverage medium in various heating temperatures. The results obtained from this study may be used in the calculations of appropriate thermal process schedules for the test beverage against the test organism. [source] Amended biochemical characteristics and phylogenetic position of Treponema mediumMOLECULAR ORAL MICROBIOLOGY, Issue 2 2003F. Nakazawa Umemoto et al. (1997, Int J Syst Bacteriol 47, pp. 67,72) proposed spirochete strain G7201, isolated from the periodontal pocket of an adult patient, as a new species, Treponema medium. They deposited this strain in the American Type Culture Collection (ATCC) as type strain ATCC 700293T. Recently, ATCC suggested that there is a discrepancy between the previous report and the results obtained by ATCC in biochemical tests on T. medium ATCC 700293T. In this study, we re-examined and verified the biochemical characteristics of T. medium. The fermentation pattern of carbohydrates of T. medium resembled that of Treponema vincentii and Treponema denticola, but T. medium was clearly differentiated from T. vincentii in the production of indole, and from T. denticola in the hydrolysis of esculin. Also, sodium dodecylsulfate,polyacrylamide gel electrophoresis (SDS-PAGE) protein profile analysis and phylogenetic comparison of 16S rDNA sequences revealed that T. medium is clearly differentiated from any established treponemal species, which supports the validity of the proposal of Treponema medium as a new species. [source] Proteomic analysis of exoproteins expressed by enterotoxigenic Staphylococcus aureus strainsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 12 2008Gabriella Pocsfalvi Dr. Abstract Pathogenic bacteria excrete a variety of virulence factors into extracellular medium and to the cell surface which have essential roles in the colonization and insurrection of the host cells, and thus reflect the degree of bacterial pathogenicity. For the exploration of virulence factors expressed in the secreted proteome fraction, different Staphylococcus aureus strains were analyzed using gel-based bottom-up proteomic approach. A total of 119 distinct proteins were identified for the enterotoxin gene cluster (egc) negative and seb gene positive S. aureus American Type Culture Collection (ATCC) 14458 strain by the use of one- and 2-DE based proteomics. Detailed analysis of enterotoxin region of the 2-D map confirmed, beside the highly expressed staphylococcal enterotoxin B (SEB), the presence of enterotoxin-like proteins SElK and SElQ previously predicted by genotyping (Sergeev et al.., J. Clin. Microbiol. 2004, 42, 2134,2143). Exoprotein patterns at the late-exponential (7,h) and stationary (24,h) phases of cellular growth show a high-level similarity in this region. Comparative analysis of enterotoxin region of five S. aureus strains including two clinical isolates (RIMD 31092 and A900322), a food derived strain (AB-8802) with highly prevalent egc positive operon and a nonenterotoxigenic reference strain (ROS) revealed the presence of different known enterotoxins and other virulence factors along with a number of core exoproteins. In addition, production of SElL (RIMD 31092) and SElP (A900322) was demonstrated for the first time at the protein level. Under the experimental conditions applied none of the enterotoxins encoded by the genes of egc operon was identified. [source] Fermentation Capabilities of Bifidobacteria Using Nondigestible Oligosaccharides, and Their Viability as Probiotics in Commercial Powder Infant FormulaJOURNAL OF FOOD SCIENCE, Issue 6 2005Darío Pérez-Conesa ABSTRACT The species Bifidobacterium bifidum, Bifidobacterium breve, Bifidobacterium longum biotype infantis (Spanish type culture collection), and Bifidobacterium longum (Morinaga nutritional foods) were evaluated in vitro in the presence of 4 commercial nondigestible oligosaccharides (NDO) (short-chain fructooligosaccharides [SCFOS] [degree of polymerization, DP: 2,3], inulin [DP: 10,0], oligofructose [DP: 2,0] and 4,-galactosyllactose [4,-GOS] [DP: 3,]). Each species was incubated anaerobically in tryptone phytone yeast (TPY) broth for 7 d with NDO. Every 24 h, bifidobacteria growth was evaluated by means of broth turbidity as optical density at 600 nm. Moreover, another sample was collected for pH culture measurement. Results showed that inulin was the substrate with the least effect on the stimulation of bifidobacteria growth and pH decrease. On the last day of incubation, the substrate 4,-GOS stimulated bacterial growth more strongly and produced a larger decrease in culture broth pH than the other substrates. On the other hand, B. bifidum and B. longum showed a greater growth with 4,-GOS. In a 2nd study, these 2 bifidobacteria species were added to a powder follow-on probiotic infant formula. The viability of the bifidobacteria during the formula's period of consumption was evaluated in 2 studies of 6 and 14 d. Both corresponded to the minimum and maximum time of consumption of the formula according to the manufacturer's directions. It was found that, although in both studies bifidobacteria counts decreased significantly (P < 0.05) with time, they were always above the recommended addition level (106 colony-forming units [CFU]/g) at the time of sale for dairy products by the Intl. Standard of Fédération Internationale de Laiterie/International Dairy Federation (FIL/IDF). Moreover, because the pH of the reconstituted formula was always close to neutrality (from 6.74 to 7.06), the number of bacteria did not drop below the recommended level. [source] New indolicidin analogues with potent antibacterial activity,CHEMICAL BIOLOGY & DRUG DESIGN, Issue 5 2004T.S. Ryge Abstract:, Indolicidin is a 13-residue antimicrobial peptide amide, ILPWKWPWWPWRR-NH2, isolated from the cytoplasmic granules of bovine neutrophils. Indolicidin is active against a wide range of microorganisms and has also been shown to be haemolytic and cytotoxic towards erythrocytes and human T lymphocytes. The aim of the present paper is two-fold. First, we examine the importance of tryptophan in the antibacterial activity of indolicidin. We prepared five peptide analogues with the format ILPXKXPXXPXRR-NH2 in which Trp-residues 4,6,8,9,11 were replaced in all positions with X = a single non-natural building block; N -substituted glycine residue or nonproteinogenic amino acid. The analogues were tested for antibacterial activity against both Staphylococcus aureus American type culture collection (ATCC) 25923 and Escherichia coli ATCC 25922. We found that tryptophan is not essential in the antibacterial activity of indolicidin, and even more active analogues were obtained by replacing tryptophan with non-natural aromatic amino acids. Using this knowledge, we then investigated a new principle for improving the antibacterial activity of small peptides. Our approach involves changing the hydrophobicity of the peptide by modifying the N-terminus with a hydrophobic non-natural building block. We prepared 22 analogues of indolicidin and [Phe4,6,8,9,11] indolicidin, 11 of each, carrying a hydrophobic non-natural building block attached to the N-terminus. Several active antibacterial analogues were identified. Finally, the cytotoxicity of the analogues against sheep erythrocytes was assessed in a haemolytic activity assay. The results presented here suggest that modified analogues of antibacterial peptides, containing non-natural building blocks, are promising lead structures for developing future therapeutics. [source] | |||||||||||||