13 research outputs found
Oligomerization states of OsPYLs.
<p>(A) SEC analyses of OsPYLs. 500 µL OsPYLs (OD<sub>280</sub> = 0.75) were applied to Superdex 200. (B) The molecular weight of OsPYL proteins were measured by static light scattering and analytical ultracentrifugation. (C) Phylogenetic tree of the 12 OsPYLs and 14 AtPYLs. Phylogenetic tree was constructed by neighbor-joining algorithms of MEGA 5.2. The labled # means the protein has no expression in <i>E.coli.</i></p
Data collection and refinement statistics.
<p>Values in parentheses are for the highest resolution shell. <i>R<sub>merge</sub></i> = Σ<sub>h</sub>Σ<sub>i</sub>|<i>I<sub>h,i</sub></i>-<i>I<sub>h</sub></i>|/Σ<sub>h</sub>Σ<sub>i</sub><i>I<sub>h,i</sub></i>, where <i>I<sub>h</sub></i> is the mean intensity of the <i>i</i> observations of symmetry related reflections of <i>h</i>. <i>R</i> = Σ|<i>F<sub>obs</sub></i>-<i>F<sub>calc</sub></i>|/Σ<i>F<sub>obs</sub></i>, where <i>F<sub>calc</sub></i> is the calculated protein structure factor from the atomic model (R<sub>free</sub> was calculated with 5% of the reflections selected).</p
Structure of the (+)-ABA-OsPYL2-OsPP2C06 ternary complex.
<p>(A) Overall structure of the (+)-ABA-OsPYL2-OsPP2C06 ternary complex. Three purple spheres in the active site of OsPP2C indicate the three Mn<sup>2+</sup> ions. (+)-ABA is shown in yellow ball-and-stick. (B) Superimposition of the structure of ABA-OsPYL2-OsPP2C06 ternary complex with ABA-AtPYL1-AtPP2C complex (PDB code: 3KDJ) and ABA-AtPYL2-AtPP2C (PDB code: 3UJL). Amino acids of ABA-AtPYL1-AtPP2C ternary complex are colored gray. Amino acids of ABA-AtPYL2-AtPP2C ternary complex are colored cyan. Amino acids of OsPP2C06 and OsPYL2 are colored blue and green, respectively. (C) The CL2 loop of OsPYL2 interacts with OsPP2C06 and partially occupies the catalytic site of OsPP2C06. Trp 339 of OsPP2C06 inserts into the hydrophobic pocket of OsPYL2 and interacts with the carbonyl oxygen of ABA through a water-mediated hydrogen bond. The red sphere indicates water molecular and the OH group in ABA. The side chain of Trp 339 is colored magenta. (D) Dissociation constant measurement between OsPYL2 and ABA binding by Isothermal Titration Calorimetry (ITC) assay.</p
The inhibition effects of OsPYLs on OsPP2C06 and OsPP2C09.
<p>The inhibition effects on OsPP2C06 and OsPP2C09 in the presence of ABA were showed as panel A and panel B, and in the absence of ABA as panel C and panel D. The phosphatase activity was measured by the Ser/Thr phosphates assay system. The details of the experiments are described in the Material and Methods. The concentrations of each OsPYL were set with molar ratio to OsPP2Cs as 1∶1 and 10∶1 in the absence of ABA (colored light and dark green). Each reaction was repeated at least three times; error bars represent standard deviations.</p
Sequence alignment of the twelve characterized OsPYLs.
<p>Secondary structural elements are indicated above the primary sequence. Helices and strands are showed as blue cylinders and arrows, respectively. The four conserved loops CL1–CL4 are highlighted by magenta lines. The key residue of OsPYL12 which are different from other OsPYLs are marked with star and colored yellow.</p
Supramolecular Chemotherapy: Carboxylated Pillar[6]arene for Decreasing Cytotoxicity of Oxaliplatin to Normal Cells and Improving Its Anticancer Bioactivity Against Colorectal Cancer
We have successfully
demonstrated that the host–guest complex of carboxylated pillar[6]Âarene
with oxaliplatin (OxPt) exhibits low cytotoxicity toward normal cells
and displays higher anticancer bioactivity against colorectal cancer
cells than OxPt itself. Owing to higher binding affinity of carboxylated
pillar[6]Âarene with spermine (SPM) than that with OxPt, the encapsulated
OxPt can be thoroughly released from its host–guest complex
by the competitive replacement with SPM. This supramolecular chemotherapy
works well both in vitro and in vivo for SPM-overexpressed cancers,
such as colorectal cancer. Compared to OxPt itself, the anticancer
bioactivity of this host–guest complex is further improved
by about 20%. Such an improvement results from the combined effect
of controlled release of OxPt from its host–guest complex and
simultaneous consumption of SPM by carboxylated pillar[6]Âarene. It
is anticipated that this supramolecular strategy may be extended to
other clinical anticancer drugs for decreasing their severe side effects
and improving their anticancer bioactivity, thus enriching the realm
of supramolecular chemotherapy
Silver Nanovoid Arrays for Surface-Enhanced Raman Scattering
Highly ordered silver nanovoid arrays are fabricated
on porous anodic alumina membranes to produce robust and cost-efficient
surface-enhanced Raman scattering (SERS) substrates. Plasmonic tunability
can be accomplished by adjusting the topography with different anode
voltages. Evenly distributed plasmonic fields, high average enhancement
factor, and excellent ambient stability due to the natural protective
layer are some of the unique advantages, and the silver nanovoid arrays
are applicable to sensing devices
External Strain Enabled Post-Modification of Nanomembrane-Based Optical Microtube Cavities
Optical
microtube cavities formed by self-rolling of pre-strained
nanomembranes feature unique optical resonance properties for both
fundamental and applied research. A post-fabrication treatment of
the microcavities made of rolled-up nanomembranes is attractive in
order to better manipulate and control the optical modes therein.
Here, we report a new approach of modifying the resonant modes by
applying external strain using a stretchable polymer substrate. The
properties of both azimuthal and higher order axial modes are systematically
investigated by varying external strain along the tube axial direction.
The post-treatment process leads to a spectral redshift and improvement
of quality factors, which is attributed to a modification of tube
shape and interlayer compactness. For tubes with axial confinement,
the measurements suggest that both the eigenenergies and mode spatial
distributions of optical axial modes get significantly modified after
applying the external strain. Our numerical calculation results show
good agreement with the experimental results. This work reports a
simple and robust strain-based modification scheme for manipulating
the resonant mode energies, mode spacing, and mode field distributions
<i>In Situ</i> Generation of Plasmonic Nanoparticles for Manipulating Photon–Plasmon Coupling in Microtube Cavities
<i>In situ</i> generation of silver nanoparticles for
selective coupling between localized plasmonic resonances and whispering-gallery
modes (WGMs) is investigated by spatially resolved laser dewetting
on microtube cavities. The size and morphology of the silver nanoparticles
are changed by adjusting the laser power and irradiation time, which
in turn effectively tune the photon–plasmon coupling strength.
Depending on the relative position of the plasmonic nanoparticles
spot and resonant field distribution of WGMs, selective coupling between
the localized surface plasmon resonances (LSPRs) and WGMs is experimentally
demonstrated. Moreover, by creating multiple plasmonic-nanoparticle
spots on the microtube cavity, the field distribution of optical axial
modes is freely tuned due to multicoupling between LSPRs and WGMs.
The multicoupling mechanism is theoretically investigated by a modified
quasipotential model based on perturbation theory. This work provides
an <i>in situ</i> fabrication of plasmonic nanoparticles
on three-dimensional microtube cavities for manipulating photon-plasmon
coupling which is of interest for optical tuning abilities and enhanced
light-matter interactions
Controlled Patterning of Plasmonic Dimers by Using an Ultrathin Nanoporous Alumina Membrane as a Shadow Mask
We report on design
and fabrication of patterned plasmonic dimer arrays by using an ultrathin
anodic aluminum oxide (AAO) membrane as a shadow mask. This strategy
allows for controllable fabrication of plasmonic dimers where the
location, size, and orientation of each particle in the dimer pairs
can be independently tuned. Particularly, plasmonic dimers with ultrasmall
nanogaps down to the sub-10 nm scale as well as a large dimer density
up to 1.0 × 10<sup>10</sup> cm<sup>–2</sup> are fabricated
over a centimeter-sized area. The plasmonic dimers exhibit significant
surface-enhanced Raman scattering (SERS) enhancement with a polarization-dependent
behavior, which is well interpreted by finite-difference time-domain
(FDTD) simulations. Our results reveal a facile approach for controllable
fabrication of large-area dimer arrays, which is of fundamental interest
for plasmon-based applications in surface-enhanced spectroscopy, biochemical
sensing, and optoelectronics