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Johns P Pereira SL Leonard AE Mukerji P Shalwitz RA Dowlati L Phillips RR Bergana MS Holton JD Das T 《Current microbiology》2007,54(2):131-135
Adenosine 5′-diphosphoribose (ADP-ribose) has been identified as a significant contributor to the anti-cytotoxic activity
of Lactobacillus bulgaricus extracts. Although the biological activities associated with the administration of probiotic bacteria and components thereof
are sometimes attributed to the peptidoglycans that comprise a substantial portion of the Gram-positive bacterial cell wall,
we found that the beta-nicotine adenine dinucleotide (NAD) hydrolysis product ADP-ribose was a significant contributor to
the observed anti-cytotoxicity in our L. bulgaricus extracts. The ADP-ribose was isolated, identified, and quantitated by high performance liquid chromatography (HPLC) and by
nuclear magnetic resonance (NMR) spectroscopy. ADP-ribose levels as low as 5 mg/L exhibited a measurable inhibition of tumor
necrosis factor alpha (TNF-α) mediated cytotoxicity in an in vitro cell assay, whereas the ADP-ribose content of the L. bulgaricus extracts often exceeded 5 mg/g dry weight. 相似文献
25.
Beyond host-pathogen interactions: microbial defense strategy in the host environment 总被引:1,自引:0,他引:1
Fialho AM Stevens FJ Das Gupta TK Chakrabarty AM 《Current opinion in biotechnology》2007,18(3):279-286
Many extracellular pathogenic bacteria colonize human or animal bodies through evasion of the host immune system, a process called host-pathogen interaction. What happens when other intruders try to invade the same host and try to establish themselves in the same niche is largely unknown. In one well-studied case, Pseudomonas aeruginosa is known to secrete the protein azurin as a weapon against such invaders as cancers, parasites and viruses. The production of such weapons by pathogenic bacteria could provide important insights into how a pathogen responds in the post-colonization state to impede other intruders for its own survival. Moreover, these molecules might find use in the pharmaceutical industry as next-generation therapeutics. 相似文献
26.
Intermittent cyclic process for enhanced biological nutrient removal treating combined chemical laboratory wastewater 总被引:1,自引:0,他引:1
The aim of this work was to assess the efficacy for simultaneous enhanced removal of nitrogen and phosphorus including organics treating combined wastewater generated from a chemical laboratory using a bench-scale Intermittent Cyclic Process Bio-reactor (ICPBR). The performance efficacy indicated that the ICPBR system with solid retention time of 15 days achieved optimum efficiency with an overall removal of ammonia nitrogen (NH4-N), phosphorus (PO4-P), and chemical oxygen demand (COD) in the range, 83-92%, 74-93%, and 90-96%, respectively. 相似文献
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Ghosh Chiranjit Patra Debashis Bala Niranjan Majumder Indira Sepay Nayim Mukhopadhyay Prabuddha Das Sukhen Kundu Rita Drew Michael G. B. León Armando Rafael Ghosh Tapas Pradhan Manik 《Biometals》2022,35(3):499-517
BioMetals - A family of dioxidovanadium(V) complexes (1–4) of the type [Na(H2O)x]+[VVO2(HL1?4)]? (x?=?4, 4.5 and 7) where HL2? represents the dianionic form of... 相似文献
28.
Chakraborty T Katsu Y Zhou LY Miyagawa S Nagahama Y Iguchi T 《The Journal of steroid biochemistry and molecular biology》2011,123(3-5):115-121
In many vertebrates, estrogens are necessary to promote the growth and differentiation of the female reproductive system during development, and have important reproductive roles in both males and females. Medaka (Oryzias latipes) has three estrogen receptor (ER) subtypes, ERα, ERβ1 and ERβ2. To evaluate the three medaka ER (mER)-ligand interactions, we applied the ERE-luciferase reporter assay system to characterize each ER subtype. In this transient transfection assay system using mammalian cells, the mER proteins displayed estrogen-dependent activation. 17β-Estradiol (E(2)) and op'-DDT showed high activation irrespective of ERs. Endosulfan also exhibited activation; with less/no transactivity measured using other pesticides, i.e., heptachlor, carbendazim, deltamethrin, acephate, dimethoate and amitraz. It was generally observed that ERβ2 had higher activation potential than ERα and ERβ1. To understand the molecular mechanism of estrogen action via ER, we also conducted E(2) treatment where we observed a trigger in ERβ2 expression upon E(2) exposure. The present data suggest that ERβ2 is essential for female gonad maintenance. The data were supported by induction of vitellogenin (VTG) mRNA in the liver and reduced VTG receptor mRNA expression in the gonad of both sexes. The present work will provide a basic tool allowing future studies to examine the receptor-ligand interactions and endocrine disrupting mechanisms, and also expands our knowledge of estrogen action on reproductive development in medaka. 相似文献
29.
Stability and microbial community structure of a partial nitrifying fixed-film bioreactor in long run 总被引:1,自引:0,他引:1
A partial nitrification system was investigated for 471 days under DO varying concentrations for assessing its stability and population dynamics. Within 130 days of operation at feed DO concentration of 1.0 ± 0.1 mg/L, more than 85% of nitrite was accumulated. Efficiency deteriorated when the feed DO concentration was increased to 4.2 ± 0.3 mg/L. Nitrite accumulation could not be re-established on decreasing feed DO to 1.0 ± 0.1 mg/L. Even at DO concentration of <0.05 mg/L, nitrate production was observed; a condition termed as anoxic nitrification. NOB was detected in the biomass even under this condition by Fluorescence in-situ hybridization (FISH) analysis. Through 16S rRNA gene sequencing a major fraction of unknown bacterial sequences closely resembling haloalkalophilic bacteria of marine origin were detected. The study indicated that these bacterial species might play a role in anoxic nitrification and that NOB could survive extreme low DO condition. 相似文献
30.
Mushroom-derived polysaccharides like β-glucan are being investigated for therapeutic properties for a long time, but their mode of action of immunomodulatory properties is not well established. In the present study, a heteroglucan from Astraeus hygrometricus designated as AE2 is investigated for its macrophage stimulatory properties using RAW 264.7 cell line. An augmentation of nitric oxide production is observed in the presence of AE2 in a dose-dependent manner due to up-regulation of iNOS (inducible NO synthase) expression; hence NF κB (nuclear factor κB) pathway is investigated. RAW 264.7 cells endured phosphorylation of Ikk (IκB kinase) and subsequently NF κB is translocated to the nucleus. Further, the PKC (protein kinase C) level of the cells enhanced significantly. We also found that AE2 could induce the phosphorylation of p38 MAPK (mitogen-activated protein kinase), ERK1/2 (extracellular-signal-regulated kinase 1/2), MEK (MAPK/ERK kinase) and JNK (c-Jun N-terminal kinase), whereas it failed to induce phosphorylation of JAK2 (Janus kinase 2) and STAT1. These results indicated that the macrophage activation by AE2 might be exerted, at least in part, via MAPKs (mitogen-activated protein kinases) pathway of signal transduction. 相似文献