An ectomycorrhizal fungus alters sensitivity to jasmonate,salicylate, gibberellin,and ethylene in host roots

The phytohormones jasmonate, gibberellin, salicylate, and ethylene regulate an interconnected reprogramming network integrating root development with plant responses against microbes. The establishment of mutualistic ectomycorrhizal symbiosis requires the suppression of plant defense responses against fungi as well as the modification of root architecture and cortical cell wall properties. Here, we investigated the contribution of phytohormones and their crosstalk to the ontogenesis of ectomycorrhizae (ECM) between grey poplar (Populus tremula x alba) roots and the fungus Laccaria bicolor. To obtain the hormonal blueprint of developing ECM, we quantified the concentrations of jasmonates, gibberellins, and salicylate via liquid chromatography–tandem mass spectrometry. Subsequently, we assessed root architecture, mycorrhizal morphology, and gene expression levels (RNA sequencing) in phytohormone-treated poplar lateral roots in the presence or absence of L. bicolor. Salicylic acid accumulated in mid-stage ECM. Exogenous phytohormone treatment affected the fungal colonization rate and/or frequency of Hartig net formation. Colonized lateral roots displayed diminished responsiveness to jasmonate but regulated some genes, implicated in defense and cell wall remodelling, that were specifically differentially expressed after jasmonate treatment. Responses to salicylate, gibberellin, and ethylene were enhanced in ECM. The dynamics of phytohormone accumulation and response suggest that jasmonate, gibberellin, salicylate, and ethylene signalling play multifaceted roles in poplar L. bicolor ectomycorrhizal development.     

Determination of B-Cell Epitopes in Patients with Celiac Disease: Peptide Microarrays

Background

Most antibodies recognize conformational or discontinuous epitopes that have a specific 3-dimensional shape; however, determination of discontinuous B-cell epitopes is a major challenge in bioscience. Moreover, the current methods for identifying peptide epitopes often involve laborious, high-cost peptide screening programs. Here, we present a novel microarray method for identifying discontinuous B-cell epitopes in celiac disease (CD) by using a silicon-based peptide array and computational methods.

Methods

Using a novel silicon-based microarray platform with a multi-pillar chip, overlapping 12-mer peptide sequences of all native and deamidated gliadins, which are known to trigger CD, were synthesized in situ and used to identify peptide epitopes.

Results

Using a computational algorithm that considered disease specificity of peptide sequences, 2 distinct epitope sets were identified. Further, by combining the most discriminative 3-mer gliadin sequences with randomly interpolated3- or 6-mer peptide sequences, novel discontinuous epitopes were identified and further optimized to maximize disease discrimination. The final discontinuous epitope sets were tested in a confirmatory cohort of CD patients and controls, yielding 99% sensitivity and 100% specificity.

Conclusions

These novel sets of epitopes derived from gliadin have a high degree of accuracy in differentiating CD from controls, compared with standard serologic tests. The method of ultra-high-density peptide microarray described here would be broadly useful to develop high-fidelity diagnostic tests and explore pathogenesis.     

The quorum sensing molecule N-acyl homoserine lactone produced by Acinetobacter baumannii displays antibacterial and anticancer properties

Secretory N-acyl homoserine lactones (AHLs) mediate quorum sensing (QS) in bacteria. AHLs are shown to be inhibitory for an unrelated group of bacteria and might mimic host signalling elements, thereby subverting the regulatory events in host cells. This study investigated the AHL produced by Acinetobacter baumannii and analysed its effect on other bacterial species and mammalian cells. Chemically characterized AHL had an m/z value of 325 with a molecular formula C₁₈H₃₁NO₄ and showed its inhibitory potential against Staphylococcus aureus. Molecular docking studies identified D-alanine-D-alanine synthetase A, a cell wall synthesizing enzyme of S. aureus having a strong binding affinity towards AHL. Electron microscopy showed the disruption and sloughing off of the S. aureus cell wall when treated with AHL. In vitro experiments revealed that this bacteriostatic AHL showed time-dependent activity and induced apoptosis in cancer cell lines. This compound could be a potential structural backbone for constructing new AHL analogues against S. aureus. The findings emphasize the need to re-evaluate all previously characterized AHLs for any additional new biological functions other than QS.     

Insights into cardiovascular risk and nutritional status in subjects with wheat-related disorders

Objective: Wheat-related disorders are a spectrum of disorders associated with different autoimmune and non-autoimmune diseases. However, it is unclear whether these wheat-related disorders lead to adverse health effects such as cardiovascular risk, nutritional deficiencies etc. The objective of the study was to explore the lipid profiles and the nutritional status of subjects with wheat-related disorders to understand the potential threat of wheat on cardiovascular risk and nutritional deficiency.

Method: A total of 1041 subjects who showed wheat-related symptoms were initially tested for the wheat protein antibody panel (Wheat Zoomer (WZ) panel and Coeliac Disease (CD) panel), then for cardiovascular panel and the micronutrient panel at Vibrant America Clinical Laboratory.

Results: Subjects with both Wheat Zoomer positivity (WZ+) and Coeliac Disease positivity (CD+) had significantly low levels of high-density lipoproteins (HDL) (279/483(57.8%) and 29/47(61.7%) respectively), but only subjects with WZ?+?had low levels of Apo A1 (44/424(9.5%)), and high levels of Omega 6 fatty acids (53/334(15.9%)). None of the micronutrients tested showed a significant imbalance in WZ?+?subjects.

Conclusion: Subjects with positive serology for WZ have deranged blood lipid profiles but did not show any significant micronutrient deficiency. Hence, our results showcase a significant association of wheat-related disorders to cardiovascular risk.     

High strain rate response of rabbit femur bones

Strain rate dependence of the mechanical response of hard tissues has led to a keen interest in their dynamic properties. The current study attempts to understand the high strain rate characteristics of rabbit femur bones. The testing was conducted using a split-Hopkinson pressure bar equipped with a high speed imaging system to capture the fracture patterns. The bones were also characterized under quasi-static compression to enable comparison with the high strain rate results. The quasi-static compressive moduli of the epiphyseal and diaphyseal regions were measured to be in the range of 2–3 and 5–7 GPa, respectively. Under high strain rate loading conditions the modulus is observed to increase with strain rate and attains values as high as 15 GPa for epiphyseal and 30 GPa for diaphyseal regions of the femur. The strength at high strain rate was measured to be about twice the quasi-static strength value. A large number of small cracks initiated on the specimen surface close to the incident bar. Coalescence of crack branches leading to fewer large cracks resulted in specimen fragmentation. In comparison, the quasi-static failure was due to shear cracking.     

Molecular docking,synthesis, and biological evaluation of naphthoquinone as potential novel scaffold for H5N1 neuraminidase inhibition

A series of dimeric naphthoquinones containing natural 2-hydroxy-1-4-naphthoquinone moiety was designed, synthesized, and evaluated against neuraminidase of H5N1 virus. p-hydroxy derivatives showed higher inhibition when compared to p-halogenated compounds. Molecular docking studies conducted with H5N1 neuraminidase clearly demonstrated different binding modes of the most active compound onto the open and closed conformations of loop 150. The results thus provide not only evidences of a novel scaffold evaluated as inhibitor, but also a rational explanation involving molecular modeling and the role of loop 150 in the binding.     

Effects of mutagens on somatic embryogenesis and plant regeneration in groundnut

The embryogenic calli (EC) were obtained from hypocotyl explants of groundnut (Arachis hypogaea L.) cultured on Murashige and Skoog (MS) medium supplemented with different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) in combination with 0.5 mg dm⁻³ 6-benzylaminopurine (BAP). The EC were exposed to γ-radiation (10–50 Gy) or treated with 1–5 mM of ethyl methane sulphonate (EMS) or sodium azide (SA). The mutated EC were subcultured on embryo induction medium containing 20 mg dm⁻³ 2,4-D. Somatic embryos (SE) developed from these calli were transferred to MS medium supplemented with BAP (2.0 mg dm⁻³) and 0.5 mg dm⁻³ 2,4-D for maturation. The well-developed embryos were cultured on germination medium consisting of MS salts with 2.0 mg dm⁻³ BAP and 0.25 mg dm⁻³ naphthaleneacetic acid (NAA). Well-developed plantlets were transferred for hardening and hardened plants produced normal flowers and set viable seeds. The fresh mass of the EC, mean number of SE per explant and regeneration percentage were higher at lower concentrations of mutagens (up to 30 Gy/3 mM). Some abnormalities in regenerated plants were observed, especially variations in leaf shape.     

Cytotoxicity and anticancer studies of Bacillus cereus and Bacillus pumilus metabolites targeting human cancer cells

The metabolites of bacteria Bacillus cereus and Bacillus pumilus isolated from soil samples in Shimoga region, Karnataka (India) were tested for cytotoxicity and anticancer properties. The various solvent extract fractions obtained from the metabolites of the two bacteria were tested for their cytotoxicity against normal human liver cell lines and 2 cancer cell lines by (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, a tetrazole) assay. The two fractions obtained from B. cereus showed high cytotoxicity. These two fractions were further screened for anticancer activity by nuclear staining studies and DNA fragmentation analysis. Both the fractions demonstrated significant activity by membrane blebbing during nuclear staining and caused the damage the DNA patterns during DNA fragmentation analysis. On the other hand, the metabolites of B. pumilus revealed toxic effect against cancer cells as well as normal ones.     

Molecular docking of phenolic compounds and screening of antioxidant and antidiabetic potential of Moringa oleifera ethanolic leaves extract from Qassim region,Saudi Arabia

IntroductionOxidative stress is crucial in diabetic pathophysiology, hence the prerequisite of ingesting naturally derived antioxidants as a remedial target. This study investigates the naturally occurring antioxidant and antidiabetic potential of Moringa oleifera ethanolic leaves extract.MethodsMoringa oleifera leaves were macerated (MOLE) by using 70% ethanol. Physiochemical and phytochemical examinations of MOLE was assayed using standard methods. The antioxidant activity was analyzed by DPPH (1, 1-diphenyl-2-picrylhydrazil) radical scavenging assay. In vitro antidiabetic was analyzed by pancreatic α-amylase enzyme inhibitory assay. The molecular docking was performed using AutoDock Vina v1.1.2 in PyRx 30.8.ResultsEthanolic extraction of MOLE by maceration technique, 14 % yield. Loss on drying, foreign organic matters and total ash value of OLE showed 0.27 w/w, 0.8 % and 19 %, respectively. Phytochemical test on MOLE confirmed starch, carbohydrate, flavonoid, gum, glycoside, saponin, tannin, and phenol presences. The total phenolic and flavonoid contents of MOLE are 260 mg GAE/g and 755 mg RUE/g of extract. MOLE (IC 50 55.6 ± 0.18 µg/mL) showed functional DPPH scavenging assay comparable to ascorbic acid (IC 50 46.71 ± 0.24 µg/mL). In the alpha-amylase inhibitory activity, Acarbose showed an IC 50 value of 19.45 ± 0.26 µg/mL, while MOLE portrayed an IC 50 value of 27.54 ± 0.07 µg/mL. Docking studies revealed that most phenolic compounds found within MOLE have minimum docking scores and high binding affinity against Human pancreatic alpha-amylase.ConclusionsThe invitro and docking results suggest that MOLE has been a viable natural bioactive source and might be a great potential source for future antidiabetic medicine.