Preparation and characterization of green fluorescent nanodiamonds for biological applications

AbstractIn the context of microbiology, recent studies show the importance of ribonucleo-protein aggregates (RNPs) for the understanding of mechanisms involved in cell responses to specific environmental conditions. The assembly and disassembly of aggregates is a dynamic process, the characterization of the stage of their evolution can be performed by the evaluation of their number. The aim of this study is to propose a method to automatically determine the count of RNPs. We show that the determination of a precise count is an issue by itself and hence, we propose three textural approaches: a classical point of view using Haralick features, a frequency point of view with generalized Fourier descriptors, and a structural point of view with Zernike moment descriptors (ZMD). These parameters are then used as inputs for a supervised classification in order to determine the most relevant. An experiment using a specific Saccharomyces cerevisiae strain presenting a fusion between a protein found in RNPs (PAB1) and the green fluorescent protein was performed to benchmark this approach. The fluorescence was observed with two-photon fluorescence microscopy. Results show that the textural approach, by mixing ZMD with Haralick features, allows for the characterization of the number of RNPs.

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Discovery and Characterization of a Bilirubin Inducible Green Fluorescent Protein From the Moray Eel Gymnothorax zonipectis

Frontiers in Marine Science ◽

10.3389/fmars.2021.678571 ◽

2021 ◽

Vol 8 ◽

Author(s):

Andrew M. Guarnaccia ◽

Sara Rose Krivoshik ◽

John S. Sparks ◽

David F. Gruber ◽

Jean P. Gaffney

Keyword(s):

Fatty Acid ◽

Binding Proteins ◽

Puget Sound ◽

Marine Organisms ◽

Fatty Acid Binding Proteins ◽

Green Fluorescence ◽

Fatty Acid Binding ◽

Green Fluorescent ◽

Moray Eel

Since the initial discovery of Aqueoria victoria’s green fluorescence off the coast of Washington’s Puget Sound, biofluorescent marine organisms have been found across the globe. The variety of colors of biofluorescence as well as the variability in the organisms that exhibit this fluorescence is astounding. The mechanisms of biofluorescence in marine organisms are also variable. To fluoresce, some organisms use fluorescent proteins, while others use small molecules. In eels, green biofluorescence was first identified in Anguilla japonica. The green fluorescence in A. japonica was discovered to be caused by a fatty acid binding protein (UnaG) whose fluorescence is induced by the addition of bilirubin. Members of this class of proteins were later discovered in Kaupichthys eels (Chlopsid FP I and Chlopsid FP II). Here, we report the discovery and characterization of the first member of this class of green fluorescent fatty acid binding proteins from the moray eel Gymnothorax zonipectis. This protein, GymFP, is 15.6 kDa with a fluorescence excitation at 496 nm and an emission maximum at 532 nm upon addition of bilirubin. GymFP is 61% homologous to UnaG and 47% homologous to Chlopsid FP I. Here, we report de novo transcriptome assembly, protein expression, and fluorescence spectroscopic characterization of GymFP. These findings extend the fluorescent fatty acid binding proteins into a third family of true eels (Anguilliformes).

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Derivation and Characterization of EGFP-Labeled Rabbit Limbal Mesenchymal Stem Cells and Their Potential for Research in Regenerative Ophthalmology

Biomedicines ◽

10.3390/biomedicines9091134 ◽

2021 ◽

Vol 9 (9) ◽

pp. 1134

Author(s):

Julia I. Khorolskaya ◽

Daria A. Perepletchikova ◽

Daniel V. Kachkin ◽

Kirill E. Zhurenkov ◽

Elga I. Alexander-Sinkler ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Stem Cell ◽

Fluorescent Protein ◽

Rabbit Model ◽

Stem Cell Markers ◽

Epithelial Stem Cells ◽

Limbal Stem Cell ◽

Green Fluorescent

The development of cell-based approaches to the treatment of various cornea pathologies, including limbal stem cell deficiency (LSCD), is an area of current interest in regenerative biomedicine. In this context, the shortage of donor material is urgent, and limbal mesenchymal stem cells (L-MSCs) may become a promising cell source for the development of these novel approaches, being established mainly within the rabbit model. In this study, we obtained and characterized rabbit L-MSCs and modified them with lentiviral transduction to express the green fluorescent protein EGFP (L-MSCs-EGFP). L-MSCs and L-MSCs-EGFP express not only stem cell markers specific for mesenchymal stem cells but also ABCG2, ABCB5, ALDH3A1, PAX6, and p63a specific for limbal epithelial stem cells (LESCs), as well as various cytokeratins (3/12, 15, 19). L-MSCs-EGFP have been proven to differentiate into adipogenic, osteogenic, and chondrogenic directions, as well as to transdifferentiate into epithelial cells. The possibility of using L-MSCs-EGFP to study the biocompatibility of various scaffolds developed to treat corneal pathologies was demonstrated. L-MSCs-EGFP may become a useful tool for studying regenerative processes occurring during the treatment of various corneal pathologies, including LSCD, with the use of cell-based technologies.

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Nanochemistry: Synthesis and Characterization of Multifunctional Nanoclinics for Biological Applications

Chemistry of Materials ◽

10.1021/cm0203013 ◽

2002 ◽

Vol 14 (9) ◽

pp. 3715-3721 ◽

Cited By ~ 243

Author(s):

Laurent Levy ◽

Yudhisthira Sahoo ◽

Kyoung-Soo Kim ◽

Earl J. Bergey ◽

Paras N. Prasad

Keyword(s):

Synthesis And Characterization ◽

Biological Applications

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Synthesis and characterization of 1,8(11),15(18),22(25)-tetraglycosylated zinc(II) phthalocyanines

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424610002343 ◽

2010 ◽

Vol 14 (06) ◽

pp. 494-498 ◽

Cited By ~ 18

Author(s):

Zafar Iqbal ◽

Alexey Lyubimtsev ◽

Michael Hanack ◽

Thomas Ziegler

Keyword(s):

Zinc Salt ◽

Synthesis And Characterization ◽

Necessary Condition ◽

Biological Applications

In continuation of our work on glycosylated phthalocyanines, a new series of 1,8(11),15(18),22(25)-tetraglycosylated zinc(II) phthalocyanines (PcZns) have been synthesized and characterized. 3-glycosylated phthalonitriles were synthesized through nitrite displacement in 3-nitrophthalonitrile with anomerically deprotected glycoses. The anomerically glycosylated phthalonitriles were then treated with hexamethyldisilazane (HMDS), trimethylsilyltriflate (TMSOTf) and zinc salt in DMF to form the corresponding acetyl-protected PcZns, followed by deprotection of acetyl groups by NaOMe in methanol/DMSO mixture. The formed unprotected tetraglycosylated PcZns are highly soluble in water, which is a necessary condition for potential biological applications.

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