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161.
Do TT Tran VN Kleiner D 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(7-8):571-575
A new purple bacterium (strain T4), capable of heterotrophic aerobic and phototrophic anaerobic growth, was isolated from waste water of a noodle factory near Hanoi, Vietnam. A comparison of 16S rDNA sequences revealed its association with the genus Rhodocista. The isolate, tentatively named "Rhodocista hanoiensis", forms cysts after growth on butyrate-containing plates at 42 degrees C. The vegetative cells form short (under aerobic conditions) or long curve-shaped rods. In contrast to other species of this genus T4 does not need any supplines (growth factors, not synthesized by the organisms). Comparative studies of T4 with Rhodocista centenaria (Rhodospirillum centenum) and Rhodocista pekingensis revealed a remarkable physiological versatility regarding nutrient spectra and survival properties of this genus. 相似文献
162.
Lipopolysaccharides containing underacylated lipid A structures exhibit reduced abilities to activate the human (h) Toll-like receptor 4 (TLR4) signalling pathway and function as potent antagonists against lipopolysaccharides bearing canonical lipid A structures. Expression of underacylated lipopolysaccharides has emerged as a novel mechanism utilized by microbial pathogens to modulate host innate immune responses. Notably, antagonistic lipopolysaccharides are prime therapeutic candidates for combating Gram negative bacterial sepsis. Penta-acylated msbB and tetra-acylated Porphyromonas gingivalis lipopolysaccharides functionally antagonize hexa-acylated Escherichia coli lipopolysaccharide-dependent activation of hTLR4 through the coreceptor, hMD-2. Here, the molecular mechanism by which these antagonistic lipopolysaccharides act at hMD-2 is examined. We present evidence that both msbB and P. gingivalis lipopolysaccharides are capable of direct binding to hMD-2. These antagonistic lipopolysaccharides can utilize at least two distinct mechanisms to block E. coli lipopolysaccharide-dependent activation of hTLR4. The main mechanism consists of direct competition between the antagonistic lipopolysaccharides and E. coli lipopolysaccharide for the same binding site on hMD-2, while the secondary mechanism involves the ability of antagonistic lipopolysaccharide-hMD-2 complexes to inhibit E. coli lipopolysaccharide-hMD-2 complexes function at hTLR4. It is also shown that both hTLR4 and hMD-2 contribute to the species-specific recognition of msbB and P. gingivalis lipopolysaccharides as antagonists at the hTLR4 complex. 相似文献
163.
Kang S Kim EY Bahn YJ Chung JW Lee do H Park SG Yoon TS Park BC Bae KH 《Cellular & molecular biology letters》2007,12(1):139-147
Oxidative stress has been implicated in the pathogenesis of neuronal degenerative diseases. It is also widely known that oxidative
stress induces mitogen-activated protein kinase (MAPK) signaling cascades. In this study, we used proteomic analysis to investigate
the role of the MAPK pathway in oxidative stress-induced neuronal cell death. The results demonstrated that several proteins,
including eukaryotic translation elongation factor 2 (eEF2) and enolase I, showed a differential expression pattern during
the neuronal cell death process, and this was MAPK pathway dependent. Several chaperone and cytoskeletal proteins including
heat shock protein 70, calreticulin, vimentin, prolyl 4-hydroxylase β polypeptide, and transgelin 2 were up-or down-regulated,
despite their expressions not depending on the MAPK pathway. These findings strongly suggest that the expressions of proteins
which play protective roles are independent of the MAPK pathway. On the other hand, eEF2 and enolase I may be the downstream
targets of the MAPK pathway. 相似文献
164.
Lim BO Lee JH Ko NY Mun SH Kim JW Kim do K Kim JD Kim BK Kim HS Her E Lee HY Choi WS 《Experimental biology and medicine (Maywood, N.J.)》2007,232(11):1425-1431
The antiallergic activity of Polygoni cuspidati radix (PR) and the mechanism of action by which it functions were investigated in this study. The extract of PR exhibited potent inhibitory activity in mast cells; its IC50 values were 62 +/- 2.1 microg/ml for RBL-2H3 mast cells and 46 +/- 3.2 microg/m for bone marrow-derived mast cells by antigen stimulation, and it also suppressed the expression of tumor necrosis factor-alpha and interleukin-4 in RBL-2H3 cells. According to the in vivo animal allergy model, it inhibited a local allergic reaction, passive cutaneous anaphylaxis, in a dose-dependent manner. With regard to its mechanism of action, PR inhibited the activating phosphorylation of Syk, a key signaling protein for the activation of mast cells. It also suppressed Akt and the mitogen-activated protein kinases ERK1/2, p38, and JNK, which are critical for the production of various inflammatory cytokines in mast cells. The results of the study indicate that the antiallergic activity of PR is mediated through the inhibition of histamine release and allergic cytokine production by the inhibition of Syk activating phosphorylation in mast cells. 相似文献
165.
Binh Tran Quang Linh Duong Tuan Chung Le Thi Kim Phuong Pham Tran Nga Bui Thi Thuy Ngoc Nguyen Anh Thuyen Tran Quang Tung Do Dinh Nhung Bui Thi 《Biochemical genetics》2022,60(2):707-719
Biochemical Genetics - The study aimed to evaluate the contribution of the FTO A/T polymorphism (rs9939609) to the prediction of the future type 2 diabetes (T2D). A population-based prospective... 相似文献
166.
Wang Hongxia Doğramacı Münevver Anderson James V. Horvath David P. Chao Wun S. 《Plant Molecular Biology Reporter》2022,40(2):359-375
Plant Molecular Biology Reporter - Camelina (Camelina sativa L. Crantz) is a short-season oilseed crop of the Brassicaceae family that consists of both summer and winter annual biotypes. Winter... 相似文献
167.
Giang Ngan Khong Pratap Kumar Pati Frédérique Richaud Boris Parizot Przemyslaw Bidzinski Chung Duc Mai Martine Bès Isabelle Bourrié Donaldo Meynard Tom Beeckman Michael Gomez Selvaraj Ishitani Manabu Anna-Maria Genga Christophe Brugidou Vinh Nang Do Emmanuel Guiderdoni Jean-Benoit Morel Pascal Gantet 《Plant physiology》2015,169(4):2935-2949
168.
Truong Quoc Phong Do Thi Thu Ha Uwe Volker Elke Hammer 《Indian journal of microbiology》2015,55(2):219-230
Reports in recent years indicate that the increasing emergence of resistance to drugs be using to TB treatment. The resistance to them severely affects to options for effective treatment. The emergence of multidrug-resistant tuberculosis has increased interest in understanding the mechanism of drug resistance in M. tuberculosis and the development of new therapeutics, diagnostics and vaccines. In this study, a label-free quantitative proteomics approach has been used to analyze proteome of multidrug-resistant and susceptible clinical isolates of M. tuberculosis and identify differences in protein abundance between the two groups. With this approach, we were able to identify a total of 1,583 proteins. The majority of identified proteins have predicted roles in lipid metabolism, intermediary metabolism, cell wall and cell processes. Comparative analysis revealed that 68 proteins identified by at least two peptides showed significant differences of at least twofolds in relative abundance between two groups. In all protein differences, the increase of some considering proteins such as NADH dehydrogenase, probable aldehyde dehydrogenase, cyclopropane mycolic acid synthase 3, probable arabinosyltransferase A, putative lipoprotein, uncharacterized oxidoreductase and six membrane proteins in resistant isolates might be involved in the drug resistance and to be potential diagnostic protein targets. The decrease in abundance of proteins related to secretion system and immunogenicity (ESAT-6-like proteins, ESX-1 secretion system associated proteins, O-antigen export system and MPT63) in the multidrug-resistant strains can be a defensive mechanism undertaken by the resistant cell.
Electronic supplementary material
The online version of this article (doi:10.1007/s12088-015-0511-2) contains supplementary material, which is available to authorized users. 相似文献169.
170.