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Caterina Holz Christiane Alexander Christina Balcke Margret Moré Annegret Auinger Maren Bauer Lauren Junker Jörg Grünwald Christine Lang Markus Pompejus 《Probiotics and antimicrobial proteins》2013,5(4):259-263
Reducing the burden of pathogenic mutans streptococci is a goal of oral health. Lactobacillus paracasei DSMZ16671, even after heat-killing, specifically co-aggregates mutans streptococci in vitro and retains this activity in human saliva. In rats, it reduces mutans streptococcal colonization of teeth and caries scores. This pilot study sought to assess the potential of heat-killed L. paracasei DSMZ16671 (pro-t-action®) to reduce levels of salivary mutans streptococci in humans, using sugar-free candies as a delivery vehicle. A randomized, placebo-controlled, double-blind in vivo study of three groups examined the short-term effect of sugar-free candies containing 0 (placebo), 1, or 2 mg/candy piece of heat-killed L. paracasei DSMZ16671 on the levels of salivary mutans streptococci determined before and after consumption of the candies. The candies were consumed 4 times during 1.5 consecutive days. Compared to the placebo group, the test groups’ saliva had significantly reduced mutans streptococci as an immediate effect. These results suggest the use of heat-killed L. paracasei DSMZ16671 in suckable candies as a method to reduce mutans streptococci in the mouth and, thereby, caries risk. We think this a new concept and strategy for caries prevention and management. 相似文献
63.
Shivange AV Serwe A Dennig A Roccatano D Haefner S Schwaneberg U 《Applied microbiology and biotechnology》2012,95(2):405-418
Phytase improves as a feed supplement the nutritional quality of phytate-rich diets (e.g., cereal grains, legumes, and oilseeds) by hydrolyzing indigestible phytate (myo-inositol 1,2,3,4,5,6-hexakis dihydrogen phosphate) and increasing abdominal absorption of inorganic phosphates, minerals, and trace elements. Directed phytase evolution was reported for improving industrial relevant properties such as thermostability (pelleting process) or activity. In this study, we report the cloning, characterization, and directed evolution of the Yersinia mollaretii phytase (Ymphytase). Ymphytase has a tetrameric structure with positive cooperativity (Hill coefficient was 2.3) and a specific activity of 1,073?U/mg which is ~10 times higher than widely used fungal phytases. High-throughput prescreening methods using filter papers or 384-well microtiter plates were developed. Precise subsequent screening for thermostable and active phytase variants was performed by combining absorbance and fluorescence-based detection system in 96-well microtiter plates. Directed evolution yielded after mutant library generation (SeSaM method) and two-step screening (in total ~8,400 clones) a phytase variant with ~20% improved thermostability (58°C for 20?min; residual activity wild type ~34%; variant ~53%) and increased melting temperature (1.5°C) with a slight loss of specific activity (993?U/mg). 相似文献
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Christian David Andreas Schmid Lorenz Adrian Annegret Wilde Katja Bühler 《Biotechnology and bioengineering》2018,115(2):300-311
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Biosynthesis of ferulic acid esters of plant cell wall polysaccharides in endomembranes from parsley cells 总被引:3,自引:0,他引:3
A microsomal preparation from suspension-cultured parsley cells is able to transfer ferulic acid from the respective CoA thioester to endogenous acceptors. The reaction is not enhanced by digitonin but stimulated by Mg2+, Ca2+ and Co2+. Spermine can partly replace divalent ions. Solubility properties and degradation by polysaccharide hydrolases suggest that the products are polymeric cell wall carbohydrates. Sucrose density gradient centrifugation revealed that the most active vesicle fraction is distinct from plasma membranes but does also not peak with IDPase. It is suggested that a subfraction of the Golgi-apparatus is the source of enzyme and acceptors. 相似文献
69.
Belastung des Kiebitzes (Vanellus vanellus) mit Dieldrin und anderen chlorierten Kohlenwasserstoffen
Martin Beyerbach Annegret Büth Walter A. Heidmann Hermann Knüwer und Harald A. Rüssel-Sinn 《Journal of Ornithology》1988,129(3):353-361
Zusammenfassung 45 Eier und 8 Kükenlebern des Kiebitzes aus den Jahren 1984 und 1986 wurden auf -, -, -HCH, HCB, DDT, Dieldrin, Endrin und PCB untersucht. Hohe Konzentrationen an Dieldrin wurden in den Eiern gefunden, während die Lebern von Kiebitzküken geringer belastet waren. Die geringen Konzentrationen der übrigen Pestizide und die mäßige an PCB entsprachen der niedrigen Trophieebene des Kiebitzes. Die Frage, ob die Belastung mit Dieldrin einen Einfluß auf den Rückgang von Kiebitzpopulationen in einigen Gebieten haben könnte, wird kurz diskutiert.
Gefördert mit Hilfe von Forschungsmitteln des Landes Niedersachsen 相似文献
The burden of Dieldrin and other chlorinated hydrocarbons on the Lapwing (Vanellus vanellus)
Summary -, -, -HCH, HCB DDT, Dieldrin, Endrin, and PCB were determined in 45 eggs and 8 livers of young Lapwings in 1984 and 1986. High concentrations of Dieldrin were found in eggs while those in livers of young Lapwings were lower. The low residues of the other pesticides and the moderate ones of PCB are in accordance with the low trophic level of the Lapwing. The probable influence of the Dieldrin burden on the decline of Lapwing populations in several regions is discussed briefly.
Gefördert mit Hilfe von Forschungsmitteln des Landes Niedersachsen 相似文献
70.
Reisenauer A Eickelberg O Wille A Heimburg A Reinhold A Sloane BF Welte T Bühling F 《Biological chemistry》2007,388(6):639-650
The TGF-beta signaling pathways are implicated in cancer. Cysteine cathepsins can contribute to the carcinogenic potential of tumor cells. The aim of this study was to investigate the regulation of cysteine cathepsin expression by TGF-beta1 and the functional implications in tumor cells. We found an upregulation of cathepsin B (CathB, 2- to 5-fold) in different myeloid tumor cells (THP-1, MonoMac-1, MonoMac-6) after incubation with TGF-beta1. No upregulation was found in monocytes, and there was suppression of CathB expression in epithelial tumor cells (A549). Increased cathepsin B activity led to enhanced carcinogenic potential, which was reflected by increased migration and invasion of the cells and resistance to inhibitor-induced apoptosis. Analysis of the TGF-beta signaling pathways showed no alterations in TGF-beta/BMP receptor expression or SMAD2/3 phosphorylation, and no influence of MAP kinase pathways. However, a reduction in SMAD1 expression was detected. The lack of BMP action on cysteine cathepsin expression in myeloid tumor cells, but not in epithelial tumor cells, suggests a defect in the Smad1/Smad5 pathway. We located a related TGF-beta1-responsive element within the first intron of the CathB gene. In conclusion, alterations in the TGF-beta1 signaling pathway lead to upregulation of CathB, which contributes to the carcinogenic potential of tumor cells. 相似文献