Recognition of saccharides in the NIR region with a novel fluorogenic boronolectin: in vitro and live cell labeling

2015 ◽  
Vol 51 (23) ◽  
pp. 4895-4898 ◽  
Author(s):  
Cecilia Samaniego Lopez ◽  
María Amparo Lago Huvelle ◽  
María Laura Uhrig ◽  
Federico Coluccio Leskow ◽  
Carla C. Spagnuolo
Keyword(s):  
Acid Derivative ◽  
Boronic Acid ◽  
Near Infrared ◽  
Detection Performance ◽  
Live Cell ◽  
Cell Labeling ◽  
Live Cells ◽  
Live Cell Labeling

The detection performance in solution and in live cells of a novel mono-boronic acid derivative of a near-infrared luminescent tricarbocyanine with OFF–ON response upon addition of saccharides.

scholarly journals A straightforward approach for bioorthogonal labeling of proteins and organelles in live mammalian cells, using a short peptide tag

2019 ◽  
Author(s):  
Inbar Segal ◽  
Dikla Nachmias ◽  
Eyal Arbely ◽  
Natalie Elia
Keyword(s):  
Mammalian Cells ◽  
Fluorescent Dyes ◽  
Specific Protein ◽  
Live Cell ◽  
Cell Labeling ◽  
Live Cells ◽  
Bioorthogonal Labeling ◽  
Labeling Approach ◽  
Genetic Code Expansion ◽  
Live Cell Labeling

AbstractIn the high-resolution microscopy era, genetic code expansion (GCE)-based bioorthogonal labeling offers an elegant way for direct labeling of proteins in live cells with fluorescent dyes. This labeling approach is currently not broadly used live cell applications, partly because it needs to be adjusted to the specific protein under study. Here, we present a generic, 14-residues long, N-terminal tag for GCE-based labeling of proteins in live mammalian cells. Using this tag, we generated a library of GCE-based organelle markers, demonstrating the applicability of the tag for labeling a plethora of proteins and organelles. Finally, we show that the HA epitope, used as a backbone in our tag, can be substituted with other epitopes and, in some cases, can be completely removed, reducing the tag length to 5 residues. The GCE-tag presented here offers a powerful, easy-to-implement tool for live cell labeling of cellular proteins with small and bright probes.

scholarly journals Inhibition of pancreatic lipase in vitro by the covalent inhibitor tetrahydrolipstatin

1988 ◽  
Vol 256 (2) ◽  
pp. 357-361 ◽  
Author(s):  
P Hadváry ◽  
H Lengsfeld ◽  
H Wolfer
Keyword(s):  
Transition State ◽  
Acid Derivative ◽  
Pancreatic Lipase ◽  
Active Site ◽  
Boronic Acid ◽  
Selective Inhibitor ◽  
Covalent Intermediate ◽  
State Form ◽  
Covalent Inhibitor

Tetrahydrolipstatin inhibits pancreatic lipase from several species, including man, with comparable potency. The lipase is progressively inactivated through the formation of a long-lived covalent intermediate, probably with a 1:1 stoichiometry. The lipase substrate triolein and also a boronic acid derivative, which is presumed to be a transition-state-form inhibitor, retard the rate of inactivation. Therefore, in all probability, tetrahydrolipstatin reacts with pancreatic lipase at, or near, the substrate binding or active site. Tetrahydrolipstatin is a selective inhibitor of lipase; other hydrolases tested were at least a thousand times less potently inhibited.

scholarly journals tdLanYFP, a yellow, bright, photostable and pH insensitive fluorescent protein for live cell imaging and FRET-based sensing strategies

2021 ◽  
Author(s):  
Y. Bousmah ◽  
H. Valenta ◽  
G. Bertolin ◽  
U. Singh ◽  
V. Nicolas ◽  
...  
Keyword(s):  
Single Molecule ◽  
Live Cell Imaging ◽  
Cell Imaging ◽  
Fluorescent Protein ◽  
Fluorescent Proteins ◽  
Yellow Fluorescent Protein ◽  
Resonance Energy ◽  
Live Cell ◽  
Live Cells

AbstractYellow fluorescent proteins (YFP) are widely used as optical reporters in Förster Resonance Energy Transfer (FRET) based biosensors. Although great improvements have been done, the sensitivity of the biosensors is still limited by the low photostability and the poor fluorescence performances of YFPs at acidic pHs. In fact, today, there is no yellow variant derived from the EYFP with a pK1/2 below ∼5.5. Here, we characterize a new yellow fluorescent protein, tdLanYFP, derived from the tetrameric protein from the cephalochordate B. lanceolatum, LanYFP. With a quantum yield of 0.92 and an extinction coefficient of 133 000 mol−1.L.cm−1, it is, to our knowledge, the brightest dimeric fluorescent protein available, and brighter than most of the monomeric YFPs. Contrasting with EYFP and its derivatives, tdLanYFP has a very high photostability in vitro and preserves this property in live cells. As a consequence, tdLanYFP allows the imaging of cellular structures with sub-diffraction resolution with STED nanoscopy. We also demonstrate that the combination of high brightness and strong photostability is compatible with the use of spectro-microscopies in single molecule regimes. Its very low pK1/2 of 3.9 makes tdLanYFP an excellent tag even at acidic pHs. Finally, we show that tdLanYFP can be a FRET partner either as donor or acceptor in different biosensing modalities. Altogether, these assets make tdLanYFPa very attractive yellow fluorescent protein for long-term or single-molecule live-cell imaging that is also suitable for FRET experiment including at acidic pH.

Effects of medium and hypothermic temperatures on preservation of isolated porcine testis cells

2010 ◽  
Vol 22 (3) ◽  
pp. 523 ◽  
Author(s):  
Yanfei Yang ◽  
Ali Honaramooz
Keyword(s):  
Trypan Blue ◽  
Cell Isolation ◽  
Live Cell ◽  
Live Cells ◽  
Cell Recovery ◽  
Trypan Blue Exclusion ◽  
Culture Studies ◽  
Porcine Testis ◽  
Peritubular Cells

The effects of medium and hypothermic temperatures on testis cells were investigated to develop a strategy for their short-term preservation. Testes from 1-week-old piglets were enzymatically dissociated for cell isolation. In Experiment 1, testis cells were stored at either room (RT) or refrigeration (RG) temperature for 6 days in one of 13 different media. Live cell recovery was assayed daily using trypan blue exclusion. In Experiment 2, three media at RG were selected for immunocytochemical and in vitro culture studies. Live cell recovery was also assayed daily for 6 days using both trypan blue exclusion and a fluorochrome assay kit. For all media tested, significantly or numerically more live cells were maintained at RG than RT. On preservation Day 3 at RG (cell isolation day as Day 0), 20% FBS-Leibovitz resulted in the highest live cell recovery (89.5 ± 1.7%) and DPBS in the lowest (60.3 ± 1.9%). On Day 6 at RG, 20% FBS- Leibovitz also resulted in the best preservation efficiency with 80.9 ± 1.8% of Day 0 live cells recovered. There was no difference in live cell recovery detected by the two viability assays. After preservation, the proportion of gonocytes did not change, whereas that of Sertoli and peritubular cells increased and decreased, respectively. After 6 days of hypothermic preservation, testis cells showed similar culture potential to fresh cells. These results show that testis cells can be preserved for 6 days under hypothermic conditions with a live cell recovery of more than 80% and after-storage viability of 88%.

Ligand-displacement-based two-photon fluorogenic probe for visualizing mercapto biomolecules in live cells, Drosophila brains and zebrafish

The Analyst ◽  
2018 ◽  
Vol 143 (14) ◽  
pp. 3433-3441 ◽  
Author(s):  
Yanfei Zhao ◽  
Yun Ni ◽  
Liulin Wang ◽  
Chenchen Xu ◽  
Chenqi Xin ◽  
...  
Keyword(s):  
Rapid Detection ◽  
Live Cell ◽  
Live Cells ◽  
Two Photon ◽  
Ligand Displacement ◽  
Cell Tissue ◽  
Fluorogenic Probe ◽  
Displacement Based

We report the Fe(iii)-based complex TPFeS which acts as a novel ligand-displacement-based TP fluorogenic probe for the rapid detection of mercapto biomolecules both in vitro and in live cell/tissue/in vivo imaging.

Frontispiece: Highly Stabletrans-Cyclooctene Amino Acids for Live-Cell Labeling

2015 ◽  
Vol 21 (35) ◽  
pp. n/a-n/a
Author(s):  
Jan-Erik Hoffmann ◽  
Tilman Plass ◽  
Ivana Nikić ◽  
Iker Valle Aramburu ◽  
Christine Koehler ◽  
...  
Keyword(s):  
Amino Acids ◽  
Live Cell ◽  
Cell Labeling ◽  
Live Cell Labeling

scholarly journals Tetrazine-Containing Amino Acid for Peptide Modification and Live Cell Labeling

PLoS ONE ◽  
2015 ◽  
Vol 10 (11) ◽  
pp. e0141918 ◽  
Author(s):  
Zhongqiu Ni ◽  
Lanxia Zhou ◽  
Xu Li ◽  
Jing Zhang ◽  
Shouliang Dong
Keyword(s):  
Amino Acid ◽  
Live Cell ◽  
Cell Labeling ◽  
Peptide Modification ◽  
Live Cell Labeling

scholarly journals Interfacing Live Cells with Surfaces: A Concurrent Control Technique for Quantifying Surface Ligand Activity

2021 ◽  
Author(s):  
Michael C. Robitaille ◽  
Joseph A. Christodoulides ◽  
Patrick Calhoun ◽  
Jeff M. Byers ◽  
Marc P. Raphael
Keyword(s):  
Cellular Adhesion ◽  
Live Cell ◽  
Control Technique ◽  
Live Cells ◽  
Chip Surface ◽  
Concurrent Control ◽  
Activity Measurements ◽  
Surface Ligand ◽  
Ligand Activity

AbstractSurface ligand activity is a key design parameter for successfully interfacing surfaces with cells - whether in the context of in vitro investigations for understanding cellular signaling pathways or more applied applications in drug delivery and medical implants. Unlike other crucial surface parameters, such as stiffness and roughness, surface ligand activity currently lacks a standardized measurement approach that can be readily paired with live cell investigations. To fill this void, we have developed a concurrent control technique for characterizing in vitro ligand surface activity. Pairs of gold-coated glass chips were biofunctionalized with RGD ligand in a parallel workflow: one chip for in vitro applications and the other for surface plasmon resonance (SPR) based RGD activity characterization. Recombinant αVβ3 integrins were injected over the SPR chip surface as mimics of the cellular membrane bound receptors and the resulting binding kinetics parameterized to quantify ligand activity. These activity measurements were correlated with cell morphological features, measured by interfacing MDA-MB-231 cells with the in vitro chip surfaces on the live cell microscope. We show that the SPR concurrent control approach has multiple advantages based on the facts that SPR is a standardized technique and has the sensitivity to measure ligand activity across the most relevant range of extracellular surface densities. Furthermore, by pairing both SPR and in vitro approaches, a comparison of the results can provide biological insights into the nature of cellular adhesion and dynamics.

Fluorogenic Protein Probes with Red or Near-Infrared Emission for Genetically Targeted Live-Cell Imaging

2020 ◽  
Author(s):  
Sylvestre P. J. T. Bachollet ◽  
Cyril Addi ◽  
Jean-Maurice Mallet ◽  
Blaise Dumat
Keyword(s):  
Live Cell Imaging ◽  
Near Infrared ◽  
Cell Imaging ◽  
Infrared Emission ◽  
Live Cell ◽  
Molecular Rotor ◽  
Model Protein ◽  
Near Infrared Emission

A series of red-emitting and near-infrared fluorogenic protein probes based on push-pull molecular rotor structures was developed. After characterization of their optical properties using Bovine Serum Albumin as a model protein, they were conjugated to a halogenoalkane ligand in order to target the protein self-labeling tag HaloTag. The interaction with HaloTag was investigated in vitro and then the most promising probes were applied to live-cell imaging in wash-free conditions using fluorogenic and chemogenetic targeting of HaloTag fusion proteins.<br>

scholarly journals A zeolite-based ship-in-a-bottle route to ultrasmall carbon dots for live cell labeling and bioimaging

2020 ◽  
Vol 2 (12) ◽  
pp. 5803-5809
Author(s):  
Lei Dong ◽  
Dehong Hu ◽  
Yanding Wang ◽  
Zonghai Sheng ◽  
Mei Hong ◽  
...  
Keyword(s):  
Carbon Dots ◽  
Live Cell ◽  
Cell Labeling ◽  
Excellent Performance ◽  
Live Cell Labeling

The smallest-pore SAPO-20 zeolite confined pyrolysis of organics afforded ultrasmall uniform carbon dots with excellent performance in bioimaging.

Sign in / Sign up

Export Citation Format

Share Document