96 research outputs found
Photostable Fluorophenyl-Substituted Cyclometalated Platinum(II) Emitters for Monitoring of Molecular Oxygen in Real Time
The effects of fluorophenyl substituents
on the photoluminescence,
redox properties, and oxygen sensing behaviors of the cyclometalated
PtÂ(II) complexes are reported. The PtÂ(II) complexes with fluorophenyl
substituents at the <i>para</i> position on the phenyl ring
of 2-phenylpyridine (ppy) exhibit higher oxygen sensitivities than
those at the <i>meta</i> position. Photodegradation tests
demonstrate that the introduction of fluorophenyl substituents can
strongly improve the photostability of cyclometalated PtÂ(II) complexes.
Fast response and recovery times of oxygen sensing films are obtained
in 3.0 s on going from 0% O<sub>2</sub> to 100% O<sub>2</sub> and
in 4.0 s on going from 100% O<sub>2</sub> to 0% O<sub>2</sub> (95%
recovery of the luminescence), respectively. The oxygen sensing films
show excellent operational stability in 4000 s saturation O<sub>2</sub>/N<sub>2</sub> cycles, which meets the requirement of monitoring
molecular oxygen in real time
Additional file 6: Figure S3. of Asymmetric somatic hybridization induces point mutations and indels in wheat
Translocations and sequence chimeras induced by somatic hybridization. (A) In the homologs SR3_2LCP192_G10 and JN177_firstas231, the identical sequence is found in positions 1187–1367 in the former allele, but at 1–181 in the other. SR3_2LCP192_G10 also harbors a large deletion with a repeat sequence CAAGAAGGA. (B) In SR3_firstas716, nucleotides 88–196 do not align with JN177_LCP139_D11 nucleotides 157–278, but their terminal sequences are identical. (TIFF 1660 kb
Kinetics of PTEN-mediated PI(3,4,5)P3 hydrolysis on solid supported membranes
<div><p>Phosphatidylinositides play important roles in cellular signaling and migration. Phosphatidylinositol-3,4,5-trisphosphate (PI(3,4,5)P3) is an important phosphatidylinositide because it acts as a secondary messenger to trigger cell movement and proliferation. A high level of PI(3,4,5)P3 at the plasma membrane is known to contribute to tumorigenesis. One key enzyme that regulates PI(3,4,5)P3 levels at the plasma membrane is phosphatase and tensin homologue deleted on chromosome 10 (PTEN), which dephosphorylates PI(3,4,5)P3 through hydrolysis to form phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2). It has been reported that PI(4,5)P2 is involved in positive feedback in the PI(3,4,5)P3 hydrolysis by PTEN. However, how PI(3,4,5)P3 dephosphorylation by PTEN is regulated, is still under debate. How other PI(3,4,5)P3-binding proteins affect the dephosphorylation kinetics catalyzed by PTEN also remains unclear. Here, we develop a fluorescent-protein biosensor approach to study how PI(3,4,5)P3 dephosphorylation is regulated by PTEN as well as its membrane-mediated feedback mechanisms. Our observation of sigmoidal kinetics of the PI(3,4,5)P3 hydrolysis reaction supports the notion of autocatalysis in PTEN function. We developed a kinetic model to describe the observed reaction kinetics, which allowed us to i) distinguish between membrane-recruitment and allosteric activation of PTEN by PI(4,5)P2, ii) account for the influence of the biosensor on the observed reaction kinetics, and iii) demonstrate that all of these mechanisms contribute to the kinetics of PTEN-mediated catalysis.</p></div
Additional file 4: Table S3. of Asymmetric somatic hybridization induces point mutations and indels in wheat
SNP and indel frequencies in unigenes participating in other processes. (DOCX 14 kb
Additional file 3: Table S2. of Asymmetric somatic hybridization induces point mutations and indels in wheat
SNP and indel frequencies in unigenes participating in metabolic processes. (DOCX 14 kb
Additional file 1: of Effectiveness and safety of bifidobacteria and berberine in people with hyperglycemia: study protocol for a randomized controlled trial
SPIRIT 2013 Checklist: recommended items to address in a clinical trial protocol and related documents*. (DOCX 591 kb
Structure–Function Relationship of a Novel PR‑5 Protein with Antimicrobial Activity from Soy Hulls
An
alkaline isoform of the PR-5 protein (designated GmOLPc) has
been purified from soybean hulls and identified by MALDI-TOF/TOF-MS.
GmOLPc effectively inhibited in vitro the growth of <i>Phytophthora
soja</i> spore and <i>Pseudomonas syringae pv glycinea</i>. The antimicrobial activity of GmOLPc should be mainly ascribed
to its high binding affinity with vesicles composed of DPPG, (1,3)-β-d-glucans, and weak endo-(1,3)-β-d-glucanase
activity. From the 3D models, predicted by the homology modeling,
GmOLPc contains an extended negatively charged cleft. The cleft was
proved to be a prerequisite for endo-(1,3)-β-d-glucanase
activity. Molecular docking revealed that the positioning of linear
(1,3)-β-d-glucans in the cleft of GmOLPc allowed an
interaction with Glu83 and Asp101 that were responsible for the hydrolytic
cleavage of glucans. Interactions of GmOLPc with model membranes indicated
that GmOLPc possesses good surface activity which could contribute
to its antimicrobial activity, as proved by the behavior of perturbing
the integrity of membranes through surface hydrophobic amino acid
residues (Phe89 and Phe94)
Additional file 1: Table S1. of Asymmetric somatic hybridization induces point mutations and indels in wheat
Details of the cDNA libraries and the contig assembly. (DOCX 11 kb
Additional file 5: Figure S2. of Asymmetric somatic hybridization induces point mutations and indels in wheat
Characterization of indels. (A) An insertion (291–764) present in an SR3 unigene has flanking sequence which matches that in its JN177 homolog. (B) A deletion (490–523) present in an SR3 unigene has flanking sequence which matches that in its JN177 homolog. (C) An insertion (143–320) present in an SR3 unigene, which harbors a run of G’s (shown in green) in both flanking sequences. (D) A deletion (664–747) present in an SR3 unigene which harbors a CATCCC repeat (shown in green) in both flanking sequences. (E) A deletion (729–868) present in an SR3 unigene, in which the identity of three nucleotides (676–678) differ between the SR3 and JN177 homologs. (TIFF 2567 kb
Theoretical model for PTEN Kinetics.
<p>YFP-PHGrp1 binds PI(3,4,5)P3 competitively with PTEN, which can only bind to and hydrolyze PI(3,4,5)P3 when Grp1 is not bound. We assume that free PI(3,4,5)P3 can be hydrolyzed via two paths, either by PI(4,5)P2-free PTEN (path 1, PTEN) or by PI(4,5)P2-bound PTEN (path 2, PTEN-PI(4,5)P2). When bound to PI(4,5)P2, PTEN can be allosterically activated and increases its hydrolysis activity towards PI(3,4,5)P3. Newly formed PI(4,5)P2 can also recruit more PTEN from solution to the membrane.</p
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