Many fluorescent proteins are currently available for biological spectroscopy and imaging measurements, allowing a wide range of biochemical and biophysical processes and interactions to be studied at various length scales. However, in applications where a small fluorescence reporter is required or desirable, the choice of fluorophores is rather limited. As such, continued effort has been devoted to the development of amino acid-based fluorophores that do not require a specific environment and additional time to mature and have a large fluorescence quantum yield, long fluorescence lifetime, good photostability, and an emission spectrum in the visible region. Herein, we show that a tryptophan analog, 4-cyanotryptophan, which differs from tryptophan by only two atoms, is the smallest fluorescent amino acid that meets these requirements and has great potential to enable in vitro and in vivo spectroscopic and microscopic measurements of proteins.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5468623 | PMC |
http://dx.doi.org/10.1073/pnas.1705586114 | DOI Listing |
Chem Sci
January 2025
School of Chemistry, University of Glasgow Joseph Black Building, University Avenue Glasgow G12 8QQ UK
To overcome the limitations of using large extrinsic chromophores for biological imaging, fluorescent unnatural α-amino acids have been widely adopted as intrinsic peptidic probes. Although various classes have been successfully utilised for imaging applications, novel amino acid probes readily prepared through operationally simple synthetic methodology are still required. Here, we report a new approach for the synthesis of unnatural α-amino acids a one-pot process involving activation and palladium-catalysed arylation of tyrosine.
View Article and Find Full Text PDFNanoscale
January 2025
College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China.
Immobilized enzymes play a crucial role in analytical sensing due to their exceptional stability and considerable commercial importance. In this study, a stable Zr-based metal-organic framework (UiO-66-NH) was prepared as an immobilization platform for horseradish peroxidase (HRP) through covalent binding. HRP@UiO-66-NH retained 75% of its activity after 10 cycles.
View Article and Find Full Text PDFCell Commun Signal
January 2025
Institute of Cancer Stem Cell, Dalian Medical University, Dalian, Liaoning Province, China.
Background: Intracellular membraneless organelles formed by liquid-liquid phase separation (LLPS) function in diverse physiological processes and have been linked to tumor-promoting properties. The nucleolus is one of the largest membraneless organelle formed through LLPS. Deubiquitylating enzymes (DUBs) emerge as novel therapeutic targets against human cancers.
View Article and Find Full Text PDFJ Fluoresc
January 2025
Department of Chemistry, Madanapalle Institute of Technology & Science, Kadiri Road, Angallu, Madanapalle, 517325, Annamayya District, Andhra Pradesh, India.
A new Rhodamine functionalised Schiff Base sensor 3',6'-bis(diethylamino)-2-((4-hydroxybenzylidene)amino)spiro[isoindoline-1,9'-xanthen]-3-one (SBRB1) was designed and synthesized. The recognition ability of sensor SBRB1 towards Hg was studied by using UV-Vis and fluorescence spectroscopy. The fluorescence results showed that the sensor SBRB1 has specific selectivity as well as sensitivity towards Hg among other competitive metal ions as the fluorescence intensity at 479 nm quenched only in the presence of Hg.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
January 2025
Key Laboratory for Microstructural Material Physics of Hebei Province, School of Science, Yanshan University, Qinhuangdao 066004 PR China. Electronic address:
2-{[3-(1H-benzoimidazol-2-yl)-2-hydroxy-5-methylbenzylidene] amino}-benzoic acid (HBIo) based on proton transfer can serve as the fluorescent probe for detecting heavy metal ions. The excited-state intramolecular proton transfer (ESIPT) reaction mechanism of the HBIo chromophore with an intramolecular asymmetric double hydrogen bond in different solvents are investigated. The reaction barrier of the ESIPT along hydrogen bond O1-H2···N3 is higher than that of ESIPT along O4-H5···N6, which indicates that the double ESIPT is a stepwise process.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!