Antifungal effects of actinomycin D on <i>Verticillium dahliae</i> via a membrane-splitting mechanism

<p>Antifungal bioassays led to the isolation of actinomycins D and A₁ from <i>Streptomyces luteus</i> TRM45540 collected from Norpo in Xinjiang, and these compounds were identified by nuclear magnetic resonance spectroscopy. The antifungal activity of actinomycin D was higher than that of actinomycin A₁. Actinomycin D clearly inhibited the spore germination, hyphal growth and biomass accumulation of <i>Verticillium dahliae</i> in a dose-dependent manner. Flow cytometric analysis with propidium iodide, total ergosterol measurement, cell leakage and scanning electron microscopy experiments demonstrated that the plasma membrane of this fungus was damaged by actinomycin D, resulting in swollen cells and cellular content leakage. Transmission electron microscopy revealed that parts of the plasma membrane infolded after being treated with actinomycin D. The antifungal activity of actinomycin D damaged the fungal plasma membrane of <i>V. dahliae</i> via a membrane-splitting mechanism, which provided new insights into the functional mechanism of actinomycin D.</p

Efficacy of dill oil on the activities of the mitochondrial ATPase of <i>A. flavus</i> cells.

<p>Significant differences (<i>p</i><0.05) between means are indicated by letters above the histogram bars. Values are means (n = 3) ± standard deviations.</p

Inhibition of ergosterol biosynthesis in <i>A. flavus</i> by dill oil.

<p>UV spectrophotometric sterol profiles of <i>A. flavus</i> cells treated with dill oil and in comparison with those of an untreated control.</p

Efficacy of dill oil on the lesion of plasma membrane of <i>A. flavus</i> cells.

<p>(A) Sequence of density plots exhibiting <i>A. flavus</i> cell size (forward scatter, FS-Lin) analyzed by flow cytometry at PMT4 channel (620 nm), and the respective percentages of PI-stained cells (right quadrant) for a series of samples treated with increasing concentrations of dill oil. (a) autofluorescence of non-treated cells; (b) fluorescence of non-treated cells stained with 1 µg/ml PI for 30 min; (c–f) cells treated with dill oil at 0.25 µl/ml (c), 0.5 µl/ml (d), 1.0 µl/ml (e), 2.0 µl/ml (f). (B) Effect of dill oil on percentage of PI-stained <i>A. flavus</i> cells analyzed by flow cytometry for 12 h and compared with an untreated control. Significant differences (<i>p</i><0.05) between means are indicated by letters above the histogram bars. Values are means (n = 3) ± standard deviations.</p

Efficacy of dill oil on the endogenous ROS in <i>A. flavus</i> cells detected by flow cytometry.

<p>(A) Dill oil-induced increase of endogenous ROS in <i>A. flavus</i> cells. (B) Effect of antioxidant Cys on dill oil-induced ROS production in <i>A. flavus</i> cells.</p

Efficacy of different concentrations of dill oil on the glucose-dependent acidification of medium in <i>A. flavus</i>.

<p>Values are means (n = 3) ± standard deviations.</p

Chemical composition, <i>N</i>-nitrosamine inhibition and antioxidant and antimicrobial properties of essential oil from <i>Coreopsis tinctoria</i> flowering tops

<p><i>Coreopsis tinctoria</i> flowering (CTF) tops from the Kunlun Mountains in Xinjing (north-western China) have been used for tea production for about a century. This study was to assess antioxidant, nitrite-scavenging and <i>N</i>-nitrosamine inhibitory and antimicrobial activities of the essential oil extracted from CTF tops. The essential oil was extracted through hydrodistillation and its chemical compositions were analysed by GC–MS. Seventy compounds of the oil were identified, representing 81.87% of total oil. The antioxidant capacities of the oil with IC₅₀ values for scavenging DPPH and ABTS were 287.66 ± 12.60 and 1.251 ± 0.127 μg mL^− 1, respectively. The nitrite-scavenging and <i>N</i>-nitrosamine inhibitory activities (IC₅₀) were 0.3912 ± 0.0127 and 0.6564 ± 0.036 μg mL^− 1, respectively. The oil has a certain antimicrobial capacity, but its capacity was weaker than that of penicillinG (24 μg mL^− 1). The oil showed antioxidant and antimicrobial capacities and had a stronger nitrite-scavenging and <i>N</i>-nitrosamine inhibitory properties.</p

Efficacy of dill oil on MMP of <i>A. flavus</i> cells.

<p>The measurements were performed by confocal laser scanning microscope (top panels) and flow cytometry (bottom panels) stained with Rh123. (A, a) Control, (B, b) Dill oil at 0.25 µl/ml, (C, c) Dill oil at 0.5 µl/ml, (D, d) Dill oil at 1.0 µl/ml, (E, e) Dill oil at 2.0 µl/ml.</p

NMR data and refinement statistics.

a<p>Values calculated for the ordered regions, as reported by PSVS <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0077020#pone.0077020-Bhattacharya1" target="_blank">[26]</a>: residues 118–183.</p>b<p>r.m.s.d calculated for residues 118–183.</p>c<p>Calculated by PSVS.</p>d<p>RPF scores <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0077020#pone.0077020-Huang1" target="_blank">[27]</a> reflecting the goodness-of-fit of the structural ensemble to the NMR data.</p

Solution NMR Structure and Histone Binding of the PHD Domain of Human MLL5

<div><p>Mixed Lineage Leukemia 5 (MLL5) is a histone methyltransferase that plays a key role in hematopoiesis, spermatogenesis and cell cycle progression. In addition to its catalytic domain, MLL5 contains a PHD finger domain, a protein module that is often involved in binding to the N-terminus of histone H3. Here we report the NMR solution structure of the MLL5 PHD domain showing a variant of the canonical PHD fold that combines conserved H3 binding features from several classes of other PHD domains (including an aromatic cage) along with a novel C-terminal α-helix, not previously seen. We further demonstrate that the PHD domain binds with similar affinity to histone H3 tail peptides di- and tri-methylated at lysine 4 (H3K4me2 and H3K4me3), the former being the putative product of the MLL5 catalytic reaction. This work establishes the PHD domain of MLL5 as a bone fide ‘reader’ domain of H3K4 methyl marks suggesting that it may guide the spreading or further methylation of this site on chromatin.</p></div