Fusarium verticillioides Pex7/20 mediates peroxisomal PTS2 pathway import, pathogenicity, and fumonisin B1 biosynthesis.

Fusarium verticillioides, a well-known fungal pathogen that causes severe disease in maize and contaminates the grains with fumonisin B1 (FB1) mycotoxin, affects the yield and quality of maize worldwide. The intrinsic roles of peroxisome targeting signal (PTS)-containing proteins in phytopathogens remain elusive. We therefore explored the regulatory role and other biological functions of the components of PTS2 receptor complex, FvPex7 and FvPex20, in F. verticillioides. We found that FvPex7 directly interacts with the carboxyl terminus of FvPex20 in F. verticillioides. PTS2-containing proteins are recognized and bound by the FvPex7 receptor or the FvPex7-Pex20 receptor complex in the cytoplasm, but the peroxisome localization of the PTS2-Pex7-Pex20 complex is only determined by Pex20 in F. verticillioides. However, we observed that some putative PTS2 proteins that interact with Pex7 are not transported into the peroxisomes, but a PTS1 protein that interacts with Pex5 was detected in the peroxisomes. Furthermore, ΔFvpex7pex20 as well as ΔFvpex7pex5 double mutants exhibited reduced pathogenicity and FB1 biosynthesis, along with defects in conidiation. The PTS2 receptor complex mutants (ΔFvpex7pex20) grew slowly on minimal media and showed reduced sensitivity to cell wall and cell membrane stress-inducing agents compared to the wild type. Taken together, we conclude that the PTS2 receptor complex mediates peroxisome matrix proteins import and contributes to pathogenicity and FB1 biosynthesis in F. verticillioides. KEY POINTS: • FvPex7 directly interacts with FvPex20 in F. verticillioides. • vThe PTS2 receptor complex is essential for the importation of PTS2-containing matrix protein into peroxisomes in F. verticillioides. • Fvpex7/pex20 is involved in pathogenicity and FB1 biosynthesis in F. verticillioides.

Direct Electrodeposition of Bimetallic Nanostructures on Co-Based MOFs for Electrochemical Sensing of Hydrogen Peroxide.

Hydrogen peroxide (H2O2) is the most significant reactive oxygen species in biological systems. Here, we reported an electrochemical sensor for the detection of H2O2 on the basis of bimetallic gold-platinum nanoparticles (Au3Pt7 NPs) supported by Co-based metal organic frameworks (Co-MOFs). First, Au3Pt7 NPs, with optimal electrocatalytic activity and accessible active surface, can be deposited on the surface of the Co-MOF-modified glassy carbon electrodes (Au3Pt7/Co-MOFs/GCE) by one-step electrodeposition method. Then, the electrochemical results demonstrated that the two-dimensional (2D) Co-MOF nanosheets as the supporting material displayed better electrocatalytic properties than the 3D Co-MOF crystals for reduction of H2O2. The fabricated Au3Pt7/2D Co-MOF exhibited high electrocatalytic activity, and the catalytic current was linear with H2O2 concentration from 0.1 µM to 5 mM, and 5-60 mM with a low detection limit of 0.02 µM (S/N = 3). The remarkable electroanalytical performance of Au3Pt7/2D Co-MOF can be attributed to the synergistic effect of the high dispersion of the Au3Pt7 NPs with the marvelous electrochemical properties and the 2D Co-MOF with high-specific surface areas. Furthermore, this sensor has been utilized to detect H2O2 concentrations released from the human Hela cells. This work provides a new method for improving the performance of electrochemical sensors by choosing the proper support materials from diverse crystal morphology materials.

DNA nanotetrahedron-assisted electrochemical aptasensor for cardiac troponin I detection based on the co-catalysis of hybrid nanozyme, natural enzyme and artificial DNAzyme.

The sensitive and accurate detection of cardiac troponin I (cTnI) is critical for myocardial infarction diagnosis. In this work, a dual-aptamer-based electrochemical (EC) biosensor was designed for cTnI detection based on the DNA nanotetrahedron (NTH) capture probes and multifunctional hybrid nanoprobes. First, the NTH-based Tro4 aptamer probes were anchored on a screen printed gold electrode (SPGE) surface through the Au-S bond, providing an enhanced spatial dimension and accessibility for capturing cTnI. Then, the hybrid nanoprobes were fabricated by using magnetic Fe3O4 nanoparticles as nanocarriers to load a large amount of cTnI-specific Tro6 aptamer, natural horseradish peroxidase (HRP), HRP-mimicking Au@Pt nanozymes and G-quadruplex/hemin DNAzyme. This signaling nanoprobes are capable of specifically recognizing the target cTnI based on the Tro6 aptamer and amplifying the signals to improve the detection sensitivity via enzymatic processes. We found the remarkable enhanced effect of EC signal to be attributed to the co-catalysis effect of hybrid nanozymes, HRP and DNAzyme. The target cTnI was sandwiched between the two types of aptamers (Tro4 and Tro6) on the electrode interface. Finally, this EC aptasensing platform exhibited great analytical performance with a wide dynamic range of 0.01-100 ng mL-1 and a low detection limit of 7.5 pg mL-1 for cTnI. The high selectivity, sensitivity and reliability of EC aptasensor can provide great potential in the clinic disease diagnostics.

Effect of Suo Quan Wan on the bladder function of aging rats based on the ß-adrenoceptor.

Suo Quan Wan (SQW) has been used to treat lower urinary tract symptoms (LUTS) in elderly patients for hundreds of years in China. ß-adrenoceptors (ß-ARs), particularly ß3-adrenoceptor (ß3-AR), was reported to be important in the bladder dysfunction of the elderly. The present study was conducted to explore the effect of ß-AR, and particularly the ß3-adrenoceptor, in aging rat bladder function in vitro and to test the therapeutic effect of SQW on LUTS in an aging rat model based on the ß3-adrenoceptor. Briefly, the bladder detrusor muscles of young (age, 3 months) and aging (age, 15 months) female rats were separated. A ß-AR non-selective agonist, isoprenaline (ISO), subtype ß3-AR agonist (BRL37344A) and ß3-AR antagonist (SR59230A) were used to define the tension change of detrusor muscles between young and aging rats in vitro. For blank controls, 12 young rats were marked, and 48 aging female rats were randomly divided into four groups as follows: Model, SQW high, SQW middle and SQW low. Following oral administration of SQW for 6 weeks in aging rats, urodynamic and bladder detrusor tests were used to evaluate the therapeutic effect of SQW. The expression of ß3-AR mRNA was investigated using reverse transcription-quantitative polymerase chain reaction. Using ISO and BRL37344A in vitro, maximum relaxation (Emax), intrinsic activity (IA), and log (50% effective concentration) (PD2) were significantly decreased in aging rats compared with that in young rats (P<0.05). Significant changes were also observed in the ß3-AR antagonist experiment, which blocked ISO-induced relaxation, with significant decreases observed in Emax, IA and PD2, and a significant increase observed in PA2 for the aging rats compared with the young controls (P<0.05). SQW was demonstrated to enhance bladder control, storage and contraction ability. Furthermore, SQW was able to increase the sensitivity and expression of ß3-AR in an aging rat. In conclusion, the decrease in ß3-AR sensitivity in aging rats and the expression resulted in bladder detrusor dysfunction. In addition, the therapeutic effect of SQW against LUTS relies on the former's effect on the urethral sphincter, bladder detrusor and ß3-AR.

[One new truxillic amide compound from Abrus mollis leaves].

The butanol extract part was extracted and isolated with water, alcohol and different organic solvents from Abrus mollis leaves. 6 compounds were isolated and purified using various column chromatographies and identified with the spectral techniques such as UV, MS, TLC, HPLC and NMR. The structures of 6 compounds were trigonelline (1), praline (2), alanine anhydride (3), (Z)-N-(4-hydroxycinnamoyl)tyrosine (4), (E)-N-(4-hydroxycinnamoyl)tyrosine (5), and abrusamide C (6). Compound 6 is a new compound, and compounds 1-4 were isolated from the plant for the first time.

[Primary Pharmacodynamic Study on Chuanping Dropping Pills].

OBJECTIVE: To study the antitussive, antiasthmatic, and expectorant effects of Chuanoing dropping pills. METHODS: Histamine-acetylcholine induced asthma, ovalbumin sensitization, pulmonary overflow, spiral strip trachea of guinea pig, lung strip of guinea pig, ammonia water or citric acid induced cough of mice, and phenol red expectoration of mice were carried out. RESULTS: Chuanping dripping pills significantly prolonged the incubation induced by histamine-acetylcholine, reduced the reaction stage of ovalbumin sensitization of guinea pig with asthma, inhibited the increase of pulmonary overflow on histamine induced asthma, reduced the contraction of smooth muscle and lung strip by histamine induced asthma on guinea pig, reduced cough times on ammonia or citrate acid caused mice, and increased the output on mice tracheal phenol red. CONCLUSIONS: Chuanping dropping pills have significant effect on antitussive, antiasthmatic and expectorant actions.

[Analysis of volatile oil in pre and post processed pieces of Eriobotrya japonica by GC-MS].

OBJECTIVE: To analyze the chemical components of the volatile oil in processed pieces of Eriobotrya japonica by GC-MS. METHODS: The volatile oil was obtained by steam distillation. The amount of the components from the volatile oil were determinated by area normalization method. The separated components were identified by GC-MS. RESULTS: The components of volatile oil in pre and post processed pieces of Eriobotrya japonica were different. CONCLUSION: The methods is reliable, stable and has good repeatability. It will provide the certain scientific methods for further evaluation quality of Eriobotrya japonica.