5 research outputs found
<i>In Cellulo</i> Mapping of Subcellular Localized Bilirubin
Bilirubin (BR) is a <i>de novo</i> synthesized metabolite of human cells. However, subcellular localization
of BR in the different organelles of human cells has been largely
unknown. Here, utilizing UnaG as a genetically encoded fluorescent
BR sensor, we report the existence of relatively BR-enriched and BR-depleted
microspaces in various cellular organelles of live cells. Our studies
indicate that (i) the cytoplasmic facing membrane of the endoplasmic
reticulum (ER) and the nucleus are relatively BR-enriched spaces and
(ii) mitochondrial intermembrane space and the ER lumen are relatively
BR-depleted spaces. Thus, we demonstrate a relationship between such
asymmetrical BR distribution in the ER membrane and the BR metabolic
pathway. Furthermore, our results suggest plausible BR-transport and
BR-regulating machineries in other cellular compartments, including
the nucleus and mitochondria
Focused Fluorescent Probe Library for Metal Cations and Biological Anions
A focused
fluorescent probe library for metal cations was developed
by combining metal chelators and picolinium/quinolinium moieties as
combinatorial blocks connected through a styryl group. Furthermore,
metal complexes derived from metal chelators having high binding affinities
for metal cations were used to construct a focused probe library for
phosphorylated biomolecules. More than 250 fluorescent probes were
screened for identifying an ultraselective probe for dTTP
Correction to Focused Fluorescent Probe Library for Metal Cations and Biological Anions
Correction to Focused Fluorescent Probe Library for
Metal Cations and Biological Anion
Homogeneous Electrochemical Assay for Protein Kinase Activity
Herein,
we report a homogeneous assay for protein kinase activity
using an electrochemistry-based probe. The approach involves a peptide
substrate conjugated with a redox tag and the phosphate-specific receptor
immobilized on an electrode surface. The peptide substrate phosphorylated
by a protein kinase binds to the receptor site of the probe, which
results in a redox current under voltammetric measurement. Our method
was successfully applied even in the presence of citrated human blood
and modified to enable a single-use, chip-based electrochemical assay
for kinase activity
An Artificial Tongue Fluorescent Sensor Array for Identification and Quantitation of Various Heavy Metal Ions
Herein, a small-molecule fluorescent
sensor array for rapid identification
of seven heavy metal ions was designed and synthesized, with its sensing
mechanism mimicking that of a tongue. The photoinduced electron transfer
and intramolecular charge transfer mechanism result in combinatorial
interactions between sensor array and heavy metal ions, which lead
to diversified fluorescence wavelength shifts and emission intensity
changes. Upon principle component analysis (PCA), this result renders
clear identification of each heavy metal ion on a 3D spatial dispersion
graph. Further exploration provides a concentration-dependent pattern,
allowing both qualitative and quantitative measurements of heavy metal
ions. On the basis of this information, a “safe-zone”
concept was proposed, which provides rapid exclusion of versatile
hazardous species from clean water samples based on toxicity characteristic
leaching procedure standards. This type of small-molecule fluorescent
sensor array could open a new avenue for multiple heavy metal ion
detection and simplified water quality analysis