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Author: Zhang, Y.; Griffiths, M.W.

Title: Induced expression of the heat shock protein genes uspA and grpE during starvation at low temperatures and their influence on thermal resistance of Escherichia coli O157:H7

Description: Heat shock proteins play an important role in protecting bacterial cells against several stresses, including starvation. In this study, the promoters for two genes encoding heat shock proteins involved in many stress responses, UspA and GrpE, were fused with the green fluorescent protein (gfp) gene. Thus, the expression of the two genes could be quantified by measuring the fluorescence emitted by the cells under different environmental conditions. The heat resistance levels of starved and nonstarved cells during storage at 5, 10, and 37 degrees C were compared with the levels of expression of the uspA and grpE genes. D52-values (times required for decimal reductions in count at 52 degrees C) increased by 11.5, 14.6, and 18.5 min when cells were starved for 3 h at 37 degrees C, for 24 h at 10 degrees C, and for 2 days at 5 degrees C, respectively. In all cases, these increases were significant (P < 0.01), indicating that the stress imposed by starvation altered the ability of E. coli O157:H7 to survive subsequent heat treatments. Thermal tolerance was correlative with the induction of UspA and GrpE. At 5 degrees C, the change in the thermal tolerance of the pathogen was positively linked to the induced expression of the grpE gene but negatively related to the expression of the uspA gene. The results obtained in this study indicate that UspA plays an important role in starvation-induced thermal tolerance at 37 degrees C but that GrpE may be more involved in regulating this response at lower temperatures. An improvement in our understanding of the molecular mechanisms involved in these cross-protection responses may make it possible to devise strategies to limit their effects.

Subject headings: Adaptation, Physiological; Bacterial Proteins/biosynthesis/*genetics; Colony Count, Microbial; Escherichia coli O157/genetics/metabolism/*physiology; *Escherichia coli Proteins; Fluorescence; Food Microbiology; *Gene Expression Regulation, Bacterial; Heat-Shock Proteins/biosynthesis/*genetics; Hot Temperature; Starvation; Time Factors

Year: 2003

Publication: Journal of Food Protection

Volume: 66

Issue: 11

Pages: 2045-2050

Full text: http://www.ingentaconnect.com/content/iafp/jfp/2003/00000066/00000011/art00012

Cited by: https://scholar.google.com/scholar?cites=15405547202539988723&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 0362-028X

ISBN:
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Author: Zhang, Z.; Ratnayaka, S.N.; Wirth, M.J.

Title: Protein UTLC-MALDI-MS using thin films of submicrometer silica particles

Description: Slides for ultra thin-layer chromatography (UTLC) were made by coating nonporous silica particles, chemically modified with polyacrylamide, as 15 mum films on glass or silicon. Three proteins, myoglobin, cytochrome c and lysozyme, are nearly baseline resolved by the mechanism of hydrophilic interaction chromatography. A plate height as low as 3 mum, with 3900 plates, is observed in 14 mm. Varying silica particle diameter among 900, 700 and 350 nm showed that decreasing particle diameter slightly improves resolution but slows the separation. Matrix-assisted laser desorption/ionization (MALDI)-MS of the proteins after separation is demonstrated by wicking sufficient sinapinic acid into the separation medium.

Subject headings: Animals; Chromatography, Thin Layer/*methods; Colloids; Hydrophobic and Hydrophilic Interactions; Microscopy, Electron, Scanning; Microspheres; Nanoparticles/chemistry; Particle Size; Proteins/chemistry/*isolation & purification; Silicon Dioxide/*chemistry; Spectrometry, Fluorescence; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/*methods

Year: 2011

Publication: Journal of Chromatography. A

Volume: 1218

Issue: 40

Pages: 7196-7202

Full text: http://www.sciencedirect.com/science/article/pii/S002196731101137X

Cited by: https://scholar.google.com/scholar?cites=7877874503681491208&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 0021-9673

ISBN:
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Author: Zhao, J.; Ma, J.; Deng, Y.; Kelly, J.A.; Kim, K.; Bang, S.-Y.; Lee, H.-S.; Li, Q.-Z.; Wakeland, E.K.; Qiu, R.; Liu, M.; Guo, J.; Li, Z.; Tan, W.; Rasmussen, A.; Lessard, C.J.; Sivils, K.L.; Hahn, B.H.; Grossman, J.M.; Kamen, D.L.; Gilkeson, G.S.; Bae, S.-C.; Gaffney, P.M.; Shen, N.; Tsao, B.P.

Title: A missense variant in NCF1 is associated with susceptibility to multiple autoimmune diseases

Description: Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease with a strong genetic component characterized by autoantibody production and a type I interferon signature. Here we report a missense variant (g.74779296G>A; p.Arg90His) in NCF1, encoding the p47phox subunit of the phagocyte NADPH oxidase (NOX2), as the putative underlying causal variant that drives a strong SLE-associated signal detected by the Immunochip in the GTF2IRD1-GTF2I region at 7q11.23 with a complex genomic structure. We show that the p.Arg90His substitution, which is reported to cause reduced reactive oxygen species (ROS) production, predisposes to SLE (odds ratio (OR) = 3.47 in Asians (Pmeta = 3.1 x 10-104), OR = 2.61 in European Americans, OR = 2.02 in African Americans) and other autoimmune diseases, including primary Sjogren's syndrome (OR = 2.45 in Chinese, OR = 2.35 in European Americans) and rheumatoid arthritis (OR = 1.65 in Koreans). Additionally, decreased and increased copy numbers of NCF1 predispose to and protect against SLE, respectively. Our data highlight the pathogenic role of reduced NOX2-derived ROS levels in autoimmune diseases.

Subject headings:

Year: 2017

Publication: Nature Genetics

Volume: 49

Issue: 3

Pages: 433-437

Full text: https://www.researchgate.net/profile/Nan_Shen10/publication/313113305_A_missense_variant_in_NCF1_is_associated_with_susceptibility_to_multiple_autoimmune_diseases/links/58949332aca27231daf8ef2b/A-missense-variant-in-NCF1-is-associated-with-susceptibility-

Cited by: https://scholar.google.com/scholar?cites=911962204946390986&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 1061-4036

ISBN:
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Author: Zheng, G.; Torres, A.M.; Price, W.S.

Title: Solvent suppression using phase-modulated binomial-like sequences and applications to diffusion measurements

Description: Two phase-modulated binomial-like pi pulses have been developed by simultaneously optimizing pulse durations and phases. In combination with excitation sculpting, both of the new binomial-like sequences outperform the well-known 3-9-19 sequence in selectivity and inversion width. The new sequences provide similar selectivity and inversion width to the W5 sequence but with significantly shorter sequence durations. When used in PGSTE-WATERGATE, they afford highly selective solvent suppression in diffusion experiments.

Subject headings: *Algorithms; *Artifacts; Complex Mixtures/*chemistry; *Diffusion; Magnetic Resonance Spectroscopy/*methods; Phase Transition; Reproducibility of Results; Sensitivity and Specificity; *Signal Processing, Computer-Assisted; Solvents/*chemistry

Year: 2008

Publication: Journal of Magnetic Resonance (San Diego, Calif. : 1997)

Volume: 194

Issue: 1

Pages: 108-114

Full text: http://www.sciencedirect.com/science/article/pii/S1090780708002000

Cited by: https://scholar.google.com/scholar?cites=3558887091587465066&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 1090-7807

ISBN:
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Author: Zheng, H.; McDonald, R.; Hall, D.G.

Title: Boronic acid catalysis for mild and selective [3+2] dipolar cycloadditions to unsaturated carboxylic acids

Description: Herein, the concept of boronic acid catalysis (BAC) for the activation of unsaturated carboxylic acids is applied in several classic dipolar [3+2] cycloadditions involving azides, nitrile oxides, and nitrones as partners. These cycloadditions can be used to produce pharmaceutically interesting, small heterocyclic products, such as triazoles, isoxazoles, and isoxazolidines. These cycloadducts are formed directly and include a free carboxylic acid functionality that can be employed for further transformations, thereby avoiding prior masking or functionalization. In all cases, BAC provides faster reactions, under milder conditions, with much improved product yields and regioselectivities. In some instances, such as triazole formation from the reaction of azides with 2-alkynoic acids, catalysis with ortho-nitrophenylboronic acid circumvents the undesirable product decarboxylation observed when using thermal activation. By using NMR spectroscopic studies, the boronic acid catalyst was shown to provide activation by a LUMO-lowering effect in the unsaturated carboxylic acid, likely via a monoacylated hemiboronic ester intermediate.

Subject headings:

Year: 2010

Publication: Chemistry (Weinheim an der Bergstrasse, Germany)

Volume: 16

Issue: 18

Pages: 5454-5460

Full text: http://onlinelibrary.wiley.com/doi/10.1002/chem.200903484/full

Cited by: https://scholar.google.com/scholar?cites=593337620339226684&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 0947-6539

ISBN:
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Author: Zheng, H.F.; Chen, L.D.; Han, X.Z.

Title: The effects of global warming on soybean yields in a long-term fertilization experiment in Northeast China

Description: Understanding how crop systems might respond to recent climate change is fundamental to the successful adaptation of efforts for sustainable agriculture. In the present paper, records over the period 1987–2004 from a long-term agroecosystem experiment carried out in Northeast China were used to explore the impacts of global warming on soybean (Glycine max (L) Merr.) yields under different controlled fertilization treatments. The results indicated that soybean yields were closely related to growing season temperatures. In most fertilization treatments, soybean yields showed a significant negative response to higher daily maximum temperature and greater diurnal temperature range (DTR), whereas they showed a significant positive response to higher daily minimum temperature. Analysis of covariance showed that these responses of soybean yields to temperature variables did not differ across fertilization treatments. Overall, soybean yields have declined significantly due to the warming trends since 1987. This has been mainly attributed to the higher daily maximum temperature. The present report demonstrates that soybean production in Northeast China may face challenges due to global warming unless potential adaptation options are adopted. The true mechanisms behind these yield impacts need further investigation to address effective agricultural adaptations for soybean systems to adapt to global warming.

Subject headings: Climate change; Agriculture; Soybeans

Year: 2009

Publication: The Journal of Agricultural Science

Volume: 147

Issue: 05

Pages: 569

Full text: http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=6101960&fileId=S002185960900879X

Cited by: https://scholar.google.com/scholar?cites=4308871342123620318&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 0021-8596

ISBN:
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Author: Zhou, W.; Li, J.H.; Chen, J.; Liu, X.Y.; Xiang, T.T.; Zhang, L.; Wan, Y.J.

Title: The red pigment prodigiosin is not an essential virulence factor in entomopathogenic Serratia marcescens

Description: Although pigments produced by pathogenic microbes are generally hypothesized as essential virulence factors, the role of red pigment prodigiosin in the pathogenesis of entomopathogenic Serratia marcescens is not clear. In this study, we analyzed the pathogenicity of different pigmented S. marcescens strains and their non-pigmented mutants in silkworms. Each pigmented strain and the corresponding non-pigmented mutants showed very similar LD50 value (statistically no difference), but caused very different symptom (color of the dead larva). Our results clearly indicated that the red pigment prodigiosin is not an essential virulence factor in entomopathogenic S. marcescens.

Subject headings: Prodigiosin; Serratia marcescens; Silkworm; Virulence

Year: 2016

Publication: Journal of Invertebrate Pathology

Volume: 136

Issue:

Pages: 92-94

Full text: http://www.sciencedirect.com/science/article/pii/S0022201116300271

Cited by: https://scholar.google.com/scholar?cites=9351671967948214376&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 0022-2011

ISBN:
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Author: Zhou, X.; Qiao, M.; Wang, F.-H.; Zhu, Y.-G.

Title: Use of commercial organic fertilizer increases the abundance of antibiotic resistance genes and antibiotics in soil

Description: The application of manure-based commercial organic fertilizers (COFs) is becoming increasingly extensive because of the expanding market for organic food. The present study examined the effects of repeated applications of chicken or swine manure-based COFs on the fate of antibiotics and antibiotic resistance genes (ARGs) in soil by conducting a soil microcosm experiment. Application of COFs significantly increased antibiotics residues, as well as the relative abundance of ARGs and the integrase gene of class 1 integrons (intIota1) in soil. Two months after each application, antibiotics and ARGs dissipated in amended soils, but they still remained at an elevated level, compared with the control. And, the accumulation of antibiotics was found due to repeated COF applications. However, the relative abundance of ARGs in most COF-amended soils did not differ significantly between the first application and the repeated application. The results imply that 2 months are not sufficient for ARGs to approach background levels, and that animal manure must be treated more effectively prior to using it in agriculture ecosystems.

Subject headings: Animals; Anti-Bacterial Agents/*analysis; Chickens; Drug Resistance, Microbial/*genetics; *Fertilizers; *Genes, Bacterial; Integrons; *Manure; Soil Microbiology; Soil Pollutants/*analysis; Swine; *Antibiotic resistance genes; *Antibiotics; *Commercial organic fertilizers; *Repeated applications; *Soil

Year: 2017

Publication: Environmental Science and Pollution Research International

Volume: 24

Issue: 1

Pages: 701-710

Full text: https://link.springer.com/article/10.1007/s11356-016-7854-z

Cited by: https://scholar.google.com/scholar?q=related:HJC-x7kGwF0J:scholar.google.com/&hl=en&as_sdt=0,16

Format: Journal Article

ISSN: 0944-1344

ISBN:
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Author: Zhou, Y.; Yang, W.; Kirberger, M.; Lee, H.-W.; Ayalasomayajula, G.; Yang, J.J.

Title: Prediction of EF-hand calcium-binding proteins and analysis of bacterial EF-hand proteins

Description: The EF-hand protein with a helix-loop-helix Ca(2+) binding motif constitutes one of the largest protein families and is involved in numerous biological processes. To facilitate the understanding of the role of Ca(2+) in biological systems using genomic information, we report, herein, our improvement on the pattern search method for the identification of EF-hand and EF-like Ca(2+)-binding proteins. The canonical EF-hand patterns are modified to cater to different flanking structural elements. In addition, on the basis of the conserved sequence of both the N- and C-terminal EF-hands within S100 and S100-like proteins, a new signature profile has been established to allow for the identification of pseudo EF-hand and S100 proteins from genomic information. The new patterns have a positive predictive value of 99% and a sensitivity of 96% for pseudo EF-hands. Furthermore, using the developed patterns, we have identified zero pseudo EF-hand motif and 467 canonical EF-hand Ca(2+) binding motifs with diverse cellular functions in the bacteria genome. The prediction results imply that pseudo EF-hand motifs are phylogenetically younger than canonical EF-hand motifs. Our prediction of Ca(2+) binding motifs provides not only an insight into the role of Ca(2+) and Ca(2+)-binding proteins in bacterial systems, but also a way to explore and define the role of Ca(2+) in other biological systems (calciomics).

Subject headings: Amino Acid Motifs; Amino Acid Sequence; Animals; Bacterial Proteins/*chemistry/metabolism; Calcium-Binding Proteins/*chemistry; *EF Hand Motifs/genetics; Evolution, Molecular; Humans; Models, Molecular; Molecular Sequence Data; Phylogeny; Sequence Alignment

Year: 2006

Publication: Proteins

Volume: 65

Issue: 3

Pages: 643-655

Full text: http://onlinelibrary.wiley.com/doi/10.1002/prot.21139/abstract?userIsAuthenticated=false&deniedAccessCustomisedMessage=

Cited by: https://scholar.google.com/scholar?cites=16259536373594132095&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 0887-3585

ISBN:
Details

Author: Zhu, Q.; Hoong, N.; Aslanian, A.; Hara, T.; Benner, C.; Heinz, S.; Miga, K.H.; Ke, E.; Verma, S.; Soroczynski, J.; Yates, J.R. 3rd; Hunter, T.; Verma, I.M.

Title: Heterochromatin-Encoded Satellite RNAs Induce Breast Cancer

Description: Heterochromatic repetitive satellite RNAs are extensively transcribed in a variety of human cancers, including BRCA1 mutant breast cancer. Aberrant expression of satellite RNAs in cultured cells induces the DNA damage response, activates cell cycle checkpoints, and causes defects in chromosome segregation. However, the mechanism by which satellite RNA expression leads to genomic instability is not well understood. Here we provide evidence that increased levels of satellite RNAs in mammary glands induce tumor formation in mice. Using mass spectrometry, we further show that genomic instability induced by satellite RNAs occurs through interactions with BRCA1-associated protein networks required for the stabilization of DNA replication forks. Additionally, de-stabilized replication forks likely promote the formation of RNA-DNA hybrids in cells expressing satellite RNAs. These studies lay the foundation for developing novel therapeutic strategies that block the effects of non-coding satellite RNAs in cancer cells.

Subject headings: BRCA1-associated proteins; DNA damage response; breast tumor formation; heterochromatic RNAs; satellite RNAs

Keywords: Heterochromatin-Encoded Satellite RNAs Induce Breast Cancer

Subject headings:

Year: 2018

Publication: Molecular Cell

Volume: 70

Issue: 5

Pages: 842-853.e7

Full text: https://www.sciencedirect.com/science/article/abs/pii/S1097276518303459

Cited by: https://scholar.google.com/scholar?cites=2263952653873276227&as_sdt=1000005&sciodt=0,16&hl=en

Format: Journal Article

ISSN: 1097-2765

ISBN:





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