scholarly journals Nile Red-Based GPCR Ligands as Ultrasensitive Probes of the Local Lipid Microenvironment of the Receptor

2021 ◽  
Vol 16 (4) ◽  
pp. 651-660
Author(s):  
Fabien Hanser ◽  
Claire Marsol ◽  
Christel Valencia ◽  
Pascal Villa ◽  
Andrey S. Klymchenko ◽  
...  
Keyword(s):  
Nile Red

En face dual fluorescence staining of fatty streaks allows observation of initiation and progression of atherosclerotic lesions

1995 ◽  
Vol 53 ◽  
pp. 864-865
Author(s):  
Anne M. Klinkner ◽  
Crystal R. Waites ◽  
Peter J. Bugelski ◽  
William D. Kerns
Keyword(s):  
Fluorescent Dyes ◽  
Nile Red ◽  
Dimethyl Formamide ◽  
High Cholesterol Diet ◽  
Methods Development ◽  
Atherosclerotic Lesions ◽  
En Face ◽  
Biochemical Evaluation ◽  
Stock Solutions ◽  
Dual Staining

A primary effort in the understanding of the progression of atherosclerotic disease has been methods development for visualization of the atherosclerotic plaque. We introduce a new method for the qualitative analysis of lipids in atherosclerotic fatty streaks which also retains those lipids for biochemical evaluation. An original aspect of the process is the ability to view an entire fatty streak en face, selectively stained for specific lipid classes within the lesion.New Zealand white rabbits were fed a high cholesterol diet(0.15%-0.3% for 14 wks). The aorta was removed and fixed in Carson's phosphate buffered formaldehyde followed by dual staining in the fluorescent dyes Nile red and filipin. Stock solutions of nile red(0.5mg/ml acetone) and filipin(2.5mg/ml dimethyl formamide) were prepared and kept at -20°C; all subsequent steps were at RT. 0.5cm × 1.0cm pieces of aorta were trimmed and adventitia removed. The pieces were then washed 3×15 min in PBS w/o CaMg, soaked in Nile red(NR)/filipin(Fl) stain(100(il NR stock + 200μl Fl stock in 10 ml PBS for 30 min, washed in PBS 3×30 min, rinsed with distilled water, mounted(Crystal Mount, Biomedia) and coverslipped and viewed by fluorescence microscopy.

The Nile-Red Sea Railroad

1907 ◽  
Vol 64 (1644supp) ◽  
pp. 8-9
Author(s):  
Harold J. Shepstone
Keyword(s):  
Red Sea ◽  
Nile Red

scholarly journals Low Glucose Mediated Fluconazole Tolerance in Cryptococcus neoformans

2021 ◽  
Vol 7 (6) ◽  
pp. 489
Author(s):  
Somanon Bhattacharya ◽  
Natalia Kronbauer Oliveira ◽  
Anne G. Savitt ◽  
Vanessa K. A. Silva ◽  
Rachel B. Krausert ◽  
...  
Keyword(s):  
Cryptococcus Neoformans ◽  
Mitochondrial Function ◽  
Efflux Pump ◽  
Nile Red ◽  
Fold Increase ◽  
Growth Conditions ◽  
Chromosome 1 ◽  
Normal Glucose ◽  
Low Glucose ◽  
Synthetic Media

Chronic meningoencephalitis is caused by Cryptococcus neoformans and is treated in many parts of the world with fluconazole (FLC) monotherapy, which is associated with treatment failure and poor outcome. In the host, C. neoformans propagates predominantly under low glucose growth conditions. We investigated whether low glucose, mimicked by growing in synthetic media (SM) with 0.05% glucose (SMlowglu), affects FLC-resistance. A > 4-fold increase in FLC tolerance was observed in seven C. neoformans strains when minimum inhibitory concentration (MIC) was determined in SMlowglu compared to MIC in SM with normal (2%) glucose (SMnlglu). In SMlowglu, C. neoformans cells exhibited upregulation of efflux pump genes AFR1 (8.7-fold) and AFR2 (2.5-fold), as well as decreased accumulation (2.6-fold) of Nile Red, an efflux pump substrate. Elevated intracellular ATP levels (3.2-fold and 3.4-fold), as well as decreased mitochondrial reactive oxygen species levels (12.8-fold and 17-fold), were found in the presence and absence of FLC, indicating that low glucose altered mitochondrial function. Fluorescence microscopy revealed that mitochondria of C. neoformans grown in SMlowglu were fragmented, whereas normal glucose promoted a reticular network of mitochondria. Although mitochondrial membrane potential (MMP) was not markedly affected in SMlowglu, it significantly decreased in the presence of FLC (12.5-fold) in SMnlglu, but remained stable in SMlowglu-growing C. neoformans cells. Our data demonstrate that increased FLC tolerance in low glucose-growing C. neoformans is the result of increased efflux pump activities and altered mitochondrial function, which is more preserved in SMlowglu. This mechanism of resistance is different from FLC heteroresistance, which is associated with aneuploidy of chromosome 1 (Chr1).

scholarly journals Analysis of Polyhydroxyalkanoates Granules in Haloferax mediterranei by Double-Fluorescence Staining with Nile Red and SYBR Green by Confocal Fluorescence Microscopy

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1582
Author(s):  
Verónica Cánovas ◽  
Salvador Garcia-Chumillas ◽  
Fuensanta Monzó ◽  
Lorena Simó-Cabrera ◽  
Carmen Fernández-Ayuso ◽  
...  
Keyword(s):  
Fluorescence Microscopy ◽  
Culture Media ◽  
Nile Red ◽  
Sybr Green ◽  
Confocal Fluorescence Microscopy ◽  
Fluorescence Staining ◽  
Haloferax Mediterranei ◽  
Optimized Protocol ◽  
Confocal Fluorescence ◽  
Pha Production

Haloferaxmediterranei is a haloarchaeon of high interest in biotechnology because it produces and mobilizes intracellular polyhydroxyalkanoate (PHA) granules during growth under stress conditions (limitation of phosphorous in the culture media), among other interesting metabolites (enzymes, carotenoids, etc.). The capability of PHA production by microbes can be monitored with the use of staining-based methods. However, the staining of haloarchaea cells is a challenging task; firstly, due to the high ionic strength of the medium, which is inappropriate for most of dyes, and secondly, due to the low permeability of the haloarchaea S-layer to macromolecules. In this work, Haloferax mediterranei is used as a halophilic archaeon model to describe an optimized protocol for the visualization and analysis of intracellular PHA granules in living cells. The method is based on double-fluorescence staining using Nile red and SYBR Green by confocal fluorescence microscopy. Thanks to this method, the capability of PHA production by new haloarchaea isolates could be easily monitored.

scholarly journals Supramolecular Nanofibers from Collagen-Mimetic Peptides Bearing Various Aromatic Groups at N-Termini via Hierarchical Self-Assembly

2021 ◽  
Vol 22 (9) ◽  
pp. 4533
Author(s):  
Tomoyuki Koga ◽  
Shinya Kingetsu ◽  
Nobuyuki Higashi
Keyword(s):  
Self Assembly ◽  
Triple Helix ◽  
Wavelength Conversion ◽  
Nile Red ◽  
Tem Analysis ◽  
Mimetic Peptides ◽  
Collagen Mimetic Peptides ◽  
Potential Applications ◽  
Hydrophobic Molecule ◽  
Emission Behavior

Self-assembly of artificial peptides has been widely studied for constructing nanostructured materials, with numerous potential applications in the nanobiotechnology field. Herein, we report the synthesis and hierarchical self-assembly of collagen-mimetic peptides (CMPs) bearing various aromatic groups at the N-termini, including 2-naphthyl, 1-naphtyl, anthracenyl, and pyrenyl groups, into nanofibers. The CMPs (R-(GPO)n: n > 4) formed a triple helix structure in water at 4 °C, as confirmed via CD analyses, and their conformations were more stable with increasing hydrophobicity of the terminal aromatic group and peptide chain length. The resulting pre-organized triple helical CMPs showed diverse self-assembly into highly ordered nanofibers, reflecting their slight differences in hydrophobic/hydrophilic balance and configuration of aromatic templates. TEM analysis demonstrated that 2Np-CMPn (n = 6 and 7) and Py-CMP6 provided well-developed natural collagen-like nanofibers and An-CMPn (n = 5–7) self-assembled into rod-like micelle fibers. On the other hand, 2Np-CMP5 and 1Np-CMP6 were unable to form nanofibers under the same conditions. Furthermore, the Py-CMP6 nanofiber was found to encapsulate a guest hydrophobic molecule, Nile red, and exhibited unique emission behavior based on the specific nanostructure. In addition to the ability of CMPs to bind small molecules, their controlled self-assembly enables their versatile utilization in drug delivery and wavelength-conversion nanomaterials.

scholarly journals Imaging and Analysis of Pseudomonas aeruginosa Swarming and Rhamnolipid Production

2011 ◽  
Vol 77 (23) ◽  
pp. 8310-8317 ◽  
Author(s):  
Joshua D. Morris ◽  
Jessica L. Hewitt ◽  
Lawrence G. Wolfe ◽  
Nachiket G. Kamatkar ◽  
Sarah M. Chapman ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Fluorescent Protein ◽  
Nile Red ◽  
Temporal Distribution ◽  
Time Lapse ◽  
Content Type ◽  
Rhamnolipid Production ◽  
Serovar Typhimurium ◽  
Surface Motility ◽  
Green Fluorescent

ABSTRACTMany bacteria spread over surfaces by “swarming” in groups. A problem for scientists who study swarming is the acquisition of statistically significant data that distinguish two observations or detail the temporal patterns and two-dimensional heterogeneities that occur. It is currently difficult to quantify differences between observed swarm phenotypes. Here, we present a method for acquisition of temporal surface motility data using time-lapse fluorescence and bioluminescence imaging. We specifically demonstrate three applications of our technique with the bacteriumPseudomonas aeruginosa. First, we quantify the temporal distribution ofP. aeruginosacells tagged with green fluorescent protein (GFP) and the surfactant rhamnolipid stained with the lipid dye Nile red. Second, we distinguish swarming ofP. aeruginosaandSalmonella entericaserovar Typhimurium in a coswarming experiment. Lastly, we quantify differences in swarming and rhamnolipid production of severalP. aeruginosastrains. While the best swarming strains produced the most rhamnolipid on surfaces, planktonic culture rhamnolipid production did not correlate with surface growth rhamnolipid production.

Solvent Polarity Studies of the Water+t-Butyl Alcohol and Water+t-Butylamine Binary Systems With the Solvatochromic Dyes Nile Red and Pyridinium-N-phenoxide Betaine, Refractometry and Permittivity Measurements

1994 ◽  
Vol 47 (9) ◽  
pp. 1771 ◽  
Author(s):  
PK Kipkemboi ◽  
AJ Easteal
Keyword(s):  
Binary Systems ◽  
Hydrophobic Interactions ◽  
Nile Red ◽  
Solvent Polarity ◽  
Butyl Alcohol ◽  
Linear Functions ◽  
Non Linear ◽  
Organic Cosolvent ◽  
Two Parameters ◽  
Polarity Parameters

The empirical solvent polarity parameters ENR and ET for the solvatochromic compounds Nile Red (1) and pyridinium-N-phenoxide betaine (2), respectively, have been determined as a function of composition for water+t -butyl alcohol and water+t-butylamine binary mixtures, over the whole composition range at 298 K. For both systems the two parameters vary with composition in a strongly non-linear fashion, and the polarity of the mixture decreases with increasing proportion of the organic cosolvent. The non-linear variation of the polarity parameters is attributed to water-cosolvent hydrophobic interactions at low cosolvent contents, and hydrogen-bonding interactions at higher cosolvent contents. Permittivity and refractive index have also been measured at 298 K for both systems, and both properties are strongly non-linear functions of composition.

Imaging lipid order changes in endosome membranes of live cells by using a Nile Red-based membrane probe

RSC Advances ◽  
2014 ◽  
Vol 4 (17) ◽  
pp. 8481-8488 ◽  
Author(s):  
Zeinab Darwich ◽  
Andrey S. Klymchenko ◽  
Denis Dujardin ◽  
Yves Mély
Keyword(s):  
Nile Red ◽  
Live Cells ◽  
Lipid Order ◽  
Membrane Probe

Changes in the composition of endosome membranes during endocytosis can be imaged in live cells with the NR12S membrane probe.

Neutral and Cationic Cyclopalladated Nile Red Metallomesogens: Synthesis and Characterization In Memory of Dr. Teresa Pugliese

2012 ◽  
Vol 558 (1) ◽  
pp. 84-92 ◽  
Author(s):  
Andreea Ionescu ◽  
Nicolas Godbert ◽  
Iolinda Aiello ◽  
Alessandra Crispini ◽  
Mauro Ghedini
Keyword(s):  
Nile Red ◽  
Synthesis And Characterization

Mixed non-covalent assemblies of ethynyl nile red and ethynyl pyrene along oligonucleotide templates

2015 ◽  
Vol 13 (2) ◽  
pp. 487-492 ◽  
Author(s):  
Philipp Ensslen ◽  
Yannic Fritz ◽  
Hans-Achim Wagenknecht
Keyword(s):  
Nile Red ◽  
Dual Fluorescence ◽  
The Difference

The mixture makes the difference: the assemblies of ethynyl pyrene and ethynyl nile red along oligonucleotide templates are highly ordered and yield dual fluorescence.

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