Fluorescent indicators for protein phosphorylation are very important in not only fundamental biology but also biomedical applications. In this study, we developed novel fluorescent and fluorescent ratiometric indicators for detection of phosphotyrosine (pTyr) derivatives. A single-chain antibody variable fragment (scFv) against phosphotyrosine was fluorescent-labeled by incorporation of tetramethylrhodamine (TAMRA)-linked nonnatural amino acid at the N- or C-terminus. The TAMRA-labeled scFv showed fluorescence enhancement upon addition of pTyr-containing peptides based on antigen-dependent fluorescence quenching effect on TAMRA. The TAMRA-labeled scFv was further fused with enhanced green fluorescent protein (EGFP) to generate a double-labeled scFv for pTyr. In the absence of antigen, fluorescence resonance energy transfer (FRET) occurred from EGFP to TAMRA but TAMRA was quenched. The antigen-binding removed the quenching of TAMRA while FRET occurred without altering its efficiency. As a result of the FRET and antigen-dependent fluorescence quenching effect, the double-labeled scFv exhibited fluorescence ratio enhancement upon the antigen-binding. The fluorescent and fluorescent ratiometric indicators obtained in this study will become a novel tool for analysis of protein phosphorylation. Moreover, this strategy utilizes antibody derivatives, and therefore, can be easily applied to other antigen-antibody pairs to generate fluorescent ratiometric indicators for various target molecules.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.jbiosc.2016.01.010 | DOI Listing |
Molecules
December 2024
State Key Laboratory of Molecular Engineering of Polymers, Laboratory of Advanced Materials, Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, Shanghai 200438, China.
With the development and improvement of analysis and detection systems, low-toxicity and harmless detection systems have received much attention, especially in the field of food detection. In this paper, a low-toxicity dual-emission molecularly imprinted fluorescence sensor (CdTe QDs@SiO/N-CDs@MIPs) was successfully designed for highly selective recognition and visual detection of tetracycline (TC) in food samples. Specifically, the non-toxic blue-emission N-doped carbon dots (N-CDs) with high luminous performance acted as the response signals to contact TC via the covalent bond between amino and carboxyl groups.
View Article and Find Full Text PDFTalanta
December 2024
Faculty of Chemistry, University of Mazandaran, Babolsar, Iran. Electronic address:
Preparation of carbon dots (CDs) from biomass waste is of great interest due to its low cost synthesis, environmental compatibility and functionalization without adding dangerous chemicals. Herein, S-doped carbon dot (SCD) was synthesized using agricultural waste as carbon precursors and modified in-situ with rhodamine B dye (SCD@RHB) to construct efficient flouresent probe. SCD@RHB was loaded into HKUST-1 metal-organic framework (SCD@RHB/HKUST-1) and the probe was employed as ratiometric flouresent (RF) sensor for the determination of ciprofloxacin (CIP) antibiotic in trace level.
View Article and Find Full Text PDFTalanta
January 2025
School of Pharmacy, Binzhou Medical University, Yantai, 264003, China. Electronic address:
Ciprofloxacin (CIP) is a commonly used antibiotic, but its abuse may cause bacterial resistance, posing a high risk to the environment and human health. Herein, based on the molecular imprinting technology, this study proposed a ratiometric fluorescence sensor employing the "post-doping" strategy, which aims to be rapid, selective, and visually easy-to-use for CIP detection to address antibiotic residues and environmental risks. Specifically, by exploiting the "antenna effect" of lanthanide metal ions (Ln), terbium (III) (Tb) chosen as a fluorescence-assisted functional monomer as well as the red emitting CdTe quantum dots (QDs) as the internal reference signal were introduced into multi-emission Tb-CdTe@SiO@MIPs (TbMIPs).
View Article and Find Full Text PDFTalanta
January 2025
State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an, 710072, PR China. Electronic address:
As an important biological indicator, the abnormity of the lysozyme level is closely related to many diseases. Herein, we devise a novel ratiometric fluorescence aptasensor for lysozyme based on the controllable excimer formation of a perylene probe, N, N'-bis(6-caproic acid)-3,4:9,10-perylene diimide (PDI) induced by cationic silver nanoparticles (Ag NPs). Binding of lysozyme aptamer with multiple phosphate groups to cationic Ag NPs strongly hinders the formation of excimer, yielding intense monomer fluorescence of PDI probe.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
December 2024
Key Laboratory of Chemical Additives for China National Light Industry, College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi'an, Shaanxi 710021, China. Electronic address:
The problem of excessive use and abuse of antibiotics in the environment and food biology is becoming increasingly prominent, and norfloxacin (NOR) is widely used as an inexpensive and broad-spectrum antibiotic drug. Therefore, rapid and effective detection of antibiotics and residues in biological samples has become a demand of the times. This article describes a ratiometric fluorescence sensor based on molecular imprinting technology for the rapid and visual detection of NOR.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!