scholarly journals Identification of Salicylic Acid Mechanism against Leaf Blight Disease in Oryza sativa by SR-FTIR Microspectroscopic and Docking Studies

Pathogens ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 652
Author(s):  
Wannaporn Thepbandit ◽  
Narendra Kumar Papathoti ◽  
Jayasimha Rayalu Daddam ◽  
Kanjana Thumanu ◽  
Supatcharee Siriwong ◽  
...  

The present study was to investigate the application and mechanism of salicylic acid (SA) as SA-Ricemate for the control of leaf blight disease using a Synchrotron Radiation-based Fourier-Transform Infra-Red (SR-FTIR) microspectroscopy and docking studies. After treating rice plants cv. KDML 105 with SA-Ricemate, the leaves were inoculated with Xanthomonas oryzae pv. oryzae, the causal agent of leaf blight, and disease severity were assessed. The leaves were also used to detect changes in endogenous SA content. The results indicated that SA-Ricemate, as an activated compound, reduced disease severity by 60% at three weeks post-inoculation and increased endogenous content by 50%. The SR-FTIR analysis of changes in the mesophyll of leaves (treated and untreated) showed that the groups of lipids, pectins, and proteins amide I and amide II occurred at higher values, and polysaccharides were shown at lower values in treated compared to untreated. Besides, docking studies were used to model a three-dimensional structure for Pathogenesis-related (PR1b) protein and further identify its interaction with SA. The results showed that ASP28, ARG31, LEU32, GLN97, and ALA93 are important residues that have strong hydrogen bonds with SA. The docking results showed that SA has a good interaction, confirming its role in expression.

2021 ◽  
Vol 23 (1) ◽  
pp. 54-59
Author(s):  
SANTOSH KUMAR ◽  
MD. NADEEM AKHTAR ◽  
SANTOSH KUMAR ◽  
MAHESH KUMAR ◽  
TRIBHUWAN KUMAR

Weather parameters play a pivotal role in the infection process and spread of pathogen. It also influences the expression of susceptibility/resistance of the host plant during post-infection phases. Therefore, an experiment was conducted for two consecutive cropping seasons (2018 &2019) to study the influence of weather parameters such as temperature, humidity, rainfall and wind direction on the emergence of alternaria leaf blight of makhana in Koshi region of Bihar. Maximum per cent disease severity of alternarialeaf blightwas observed during the peak monsoon months (June to August). Highest disease severity of leaf blight (14.80% & 15.7%) was observed in the mid June during crop season, 2018 and 2019. High temperature (36.9oC & 38.1oC), and relative humidity (94% & 96.4%) of both the year 2018 and 2019 were found correlated with higher severity to alternaria leaf blight. Similarly average HTR values (3.1) were also found correlated with the average high temperature and relative humidity of both years (2018 and 2019) in terms of severity of leaf blight disease. Maximum temperatures, relative humidity and rainfall exhibited strong positive linear relationship and influenced the occurrence of alternaria leaf blight disease significantly. We also developed a geo-phytopathological model for the prediction of alternaria leaf blight disease of makhana on the basis of congenial mean temperature and relative humidity.


Author(s):  
SANGEETA RANI ◽  
KAVITA GAHLOT ◽  
ARVIND KUMAR

Objective: The purpose of this study was to investigate the diabetic effect of phytocompounds isolated from Cressa cretica Linn. using spectroscopic analysis and molecular docking studies. Methods: Coarse powder of the whole plant of C. cretica was extracted with methanol, extracted part was subjected to silica column isolation, and two compounds: 2-Isopropyl-4-(1-methyl-dodeca-2,4-dienyloxy)-benzene-1,3,5-triol (Compound CN-01) and 11-Methyl-dodeca-2,4,6,8,10-pentenoic acid 2,3-dihydroxy-5-methyl-phenyl ester (Compound CN-02) were isolated in pure form. The three-dimensional structure of target protein was downloaded from PDB (www.rcsb.org) Protein Data Bank, Ligand file CN – 01 and CN – 02 were converted to MDL Molfile (V2000) format using ChemSketch 2017.2.1. These files could not be used directly in AutoDock 4.0 tools; thus, they were first converted to PDB files using an open babel tool. Results: Compounds were revealed through spectroscopic analysis and screened using AutoDock 4.0 tools. Docking study recommended that CN – 01 and CN – 02 an existing phytochemical from the plant of C. cretica had the highest fitness docking score and hence could be a potent antidiabetic drug. Conclusion: In this investigation, we docked the receptor (glycogen phosphorylase protein) holds a promising lead target formation against diabetes based on molecular docking analysis (minimum hydrogen bond length and maximum docked score). Thus, these compounds can be effectively used as drugs for treating diabetes which is predicted on the basis of docking scores.


2020 ◽  
Vol 21 (16) ◽  
pp. 5767
Author(s):  
Yuting Hu ◽  
Shengfu Zhong ◽  
Min Zhang ◽  
Yinping Liang ◽  
Guoshu Gong ◽  
...  

Photosynthesis is not only a primary generator of reactive oxygen species (ROS) but also a component of plant defence. To determine the relationships among photosynthesis, ROS, and defence responses to powdery mildew in wheat, we compared the responses of the Pm40-expressing wheat line L658 and its susceptible sister line L958 at 0, 6, 12, 24, 48, and 72 h post-inoculation (hpi) with powdery mildew via analyses of transcriptomes, cytology, antioxidant activities, photosynthesis, and chlorophyll fluorescence parameters. The results showed that H2O2 accumulation in L658 was significantly greater than that in L958 at 6 and 48 hpi, and the enzymes activity and transcripts expression of peroxidase and catalase were suppressed in L658 compared with L958. In addition, the inhibition of photosynthesis in L658 paralleled the global downregulation of photosynthesis-related genes. Furthermore, the expression of the salicylic acid-related genes non-expressor of pathogenesis related genes 1 (NPR1), pathogenesis-related 1 (PR1), and pathogenesis-related 5 (PR5) was upregulated, while the expression of jasmonic acid- and ethylene-related genes was inhibited in L658 compared with L958. In conclusion, the downregulation of photosynthesis-related genes likely led to a decline in photosynthesis, which may be combined with the inhibition of peroxidase (POD) and catalase (CAT) to generate two stages of H2O2 accumulation. The high level of H2O2, salicylic acid and PR1 and PR5 in L658 possible initiated the hypersensitive response.


Author(s):  
Mandah Cicelia Takor ◽  
Ekwa Yawa Monono ◽  
Ojong Agbor Ntane ◽  
Jemimah Evenye Ngale ◽  
Lum A. Fontem

Taro leaf blight (TLB), a major disease of taro plant caused by Phytophthora colocasiae, a pseudo-fungus, that occurs in many taro producing areas, especially in the South West of Cameroon. A Survey was conducted to assess farmers’ knowledge, as well as to determine the incidence and the severity of the disease in taro fields. Structured questionnaires were administered in selected locations (Bokova, Ekona, Muea, Mile 16, Mutengene, and Likomba) of taro production. Two farms were selected with two quadrats of 64 m2 each were carved to assess disease incidence and severity on taro. The number of plants infected with taro leaf blight were counted and the area of the affected leaves measured was used to evaluate the disease incidence and disease severity. Data collected were subjected to ANOVA for complete randomized design and the means were compared using Tukey test at 0.05 probability levels. The results revealed that most of the farmers could identify the disease while practicing cultural methods in controlling the disease. The results also revealed significant differences (p = 0.001) in disease incidence and disease severity in all the localities, with Mile 16 showing the highest percentage mean of 96.53% and 85.59%, respectively. The severity scored showed high infection range of 3 – 3.95 in all locations except in Likomba (2.60).  It could be concluded from the results that there were high prevalence of taro leaf blight disease in Fako Division. Good management strategies are therefore required to control Taro leaf blight and improve taro production in the area.


2021 ◽  
pp. 192-203
Author(s):  
Mansi Agrahari ◽  
Kanu Megha ◽  
Kajal Dahiya ◽  
Ila Sharma ◽  
Ankur Sharma ◽  
...  

Objective: In-silico methods to find and characterize the ligands against the active site of tau protein which could assist in the therapeutics of Alzheimer's disease. Methods: The aid of various bioinformatic tools such as phylogenetic analysis, homology modeling, and active site prediction led to the molecular docking analysis of the major malefactor for Alzheimer’s disease ‘microtubule- associated tau protein’. A three-dimensional structure of microtubule-related tau protein was created, and the Ramachandran plot was acquired for quality appraisal. Results: Procheck showed 62.95 of residues in the most preferred region with 20% residues in the additional allowed region and 5.7 % in the disallowed region of microtubule-associated tau protein. Screenings of the particles were done dependent on Lipinski's standard of five. Conclusion: Genistein, Hesperidin, and epigallocatechin-3 are the potential ligands in regulating microtubule-related tau protein and Epigallocatechin-3 gallate is the most potent among them and the most elevated negative free vitality of official with the maximum interacting surface territory throughout docking studies.


Author(s):  
D. Sivakumar ◽  
G. Geetha

Objective: In the present study, a novel series of 1, 3, 4-thiadiazole derivatives were docked against the mycobacterium tuberculosis protein kinase G. 1, 3, 4–thiadiazole derivatives with a modified primary amine group at 5th position were used for docking studies.Methods: The three-dimensional structure of the protein was obtained from PDB, and its active sites were predicted. The structures of all the compounds were drawn using chemdraw software version 8.0. The docking studies were done by using schrödinger software against the enzyme protein kinase G. Totally eighteen compounds was synthesized based on glide scoreResults: In this Docking study the thiadiazole analogues were showing good binding energy. The amino acids residues GLU588, SER412, GLY410 and GLU 628 in the kinase domain active site form hydrogen bonds with the ligand.Conclusion: The compounds D34, D16, D7, D25, D15, and D27 showed better interaction with protein kinase G (pknG) more than the other drug molecules


2020 ◽  
Vol 21 ◽  
Author(s):  
Luciana Scotti ◽  
Poliane da Silva Calixto ◽  
Mirian G. S. Stiebbe Salvadori ◽  
Reinaldo Nóbrega de Almeida ◽  
Mayara dos Santos Maia ◽  
...  

Background: Natural products, such as phenylpropanoids, which are found in essential oils derived from aromatic plants, have been explored during non-clinical psychopharmacology studies, to discover new molecules with relevant pharmacological activities in the central nervous system, especially antidepressant and anxiolytic activities. Major depressive disorder is a highly debilitating psychiatric disorder and is considered to be a disabling public health problem, worldwide, as a primary factor associated with suicide. Current clinically administered antidepressants have late-onset therapeutic actions, are associated with several side effects, and clinical studies have reported that some patients do not respond well to treatment or reach complete remission. Objective: To review important new targets for antidepressant activity and to select phenylpropanoids with antidepressant activity, using Molegro Virtual Docker and Ossis Data Warris, and to verify substances with more promising antidepressant activity. Results and Conclusion: We conducted an in silico molecular modeling study, based on homology, to determine the three-dimensional structure the 5-hydroxytryptamine 2A receptor (5-HT2AR), then performed molecular docking studies and examined the predisposition for cytotoxicity risk among identified molecules. We obtained a model for 5-HT2AR homology, with satisfactory results, indicating the good stereochemical quality of the model. The phenylpropanoid 4- allyl-2,6-dimethoxyphenol showed the lowest binding energy for 5-HT2AR, with results relevant to the L-arginine/nitric oxide (NO)/cGMP pathway, and showed no toxicity within the parameters of mutagenicity, carcinogenicity, reproductive system toxicity, and skin-tissue irritability, when evaluated in silico; therefore, this molecule can be considered promising for the investigation of antidepressant activity.


Author(s):  
Sunil Kumar Suryawanshi ◽  
Usha Chouhan

 Objective: In this study, antimicrobial activity was predicted against novel antimicrobial target 1SDE receptor to understand the structural feature of predicted peptides using machine learning approach from Ocimum tenuiflorum. Methods: Protein sequences from O. tenuiflorum were digested using peptide cutter and further processed for the prediction of antimicrobial peptide (AMP) through AMP predictor tool of CAMP which have multidimensional algorithms such as support vector machine, artificial neural network, random forest, and discriminant analysis. After analyzing various peptides, only four peptides were predicted as antimicrobial in nature. Furthermore, the three-dimensional structure of different potential peptides was generated with the help of Pepfold-3.0 server followed by protein-peptide docking studies with novel target receptor with the help of PatchDock, FireDock webserver, and Hex 8.0 software. Interactions were further visualized using Discovery Studio Client 2.5 software tool.Results: This study revealed that peptide 2 resulted higher score in PatchDock and FireDock and also Hex 8.0 provides E total value of −430.18 which is higher than that of peptide 1 with −381.07, peptide 3 with −416.86, and peptide 4 with −407.94.Conclusion: The peptide predicted in this study has potential to act as effective AMP against target receptor and also utilize other antimicrobial target.


Plant Disease ◽  
2014 ◽  
Vol 98 (12) ◽  
pp. 1741-1741 ◽  
Author(s):  
M. Elliott ◽  
G. A. Chastagner ◽  
K. P. Coats ◽  
P. Sikdar ◽  
C. L. Xiao

In recent years, a leaf blight disease, consisting of browned, desiccated leaves occurring mainly in the lower parts of the canopy, has been observed during wet springs on Pacific madrone (Arbutus menziesii) in western Washington and Oregon. In May 2009 and 2011, severe outbreaks occurred and symptomatic leaves from madrones growing in the region were sampled to determine the causal agent. Two symptoms, leaf necrosis or blotching along the edges and tips of the leaves, and leaf spot, were observed. Small segments of diseased tissue were cut from the leaves, surface-disinfected, rinsed, and plated on malt extract agar. Fifty percent of the leaf blotch and 30% of leaf spot samples yielded a fungus that was fast-growing (20 mm diameter in 4 days at 25°C) and produced colonies that were a pale gray with dark gray reverse and a felty texture. On potato dextrose agar (PDA), pycnidia formed and exuded conidia in peach-colored droplets after 2 weeks under room temperature and light conditions. Pycnidia were spherical and 12.5 to 39.8 μm, average 24.2 μm in diameter. Conidia were hyaline, ovoid, and 5.8 to 8.5 × 3.1 to 4.7 μm (average 7.0 × 3.7 μm). The fungus was identified as Phacidiopycnis washingtonensis based on its morphology (1). To confirm the identity, the internal transcribed spacer (ITS) region of the rDNA was amplified with ITS1/ITS4 primers (2) and sequenced (GenBank Accession Nos. JQ743784 to 86). BLAST analysis showed 100% nucleotide identity with those of P. washingtonensis in GenBank (AY608648). The fungus was also isolated from lesions on green shoots and the petiole and leaf blade of dead attached leaves. To test pathogenicity, 3-year-old Pacific madrone seedlings (three for each isolate) were inoculated with five isolates of the fungus and maintained in the greenhouse (25°C); the experiment was conducted twice. Five leaves from each tree were cold injured (–50°C) at a marked 5 × 5 mm2 area with a commercial aerosol tissue freezing product prior to inoculation and five leaves were not cold injured. A 5-mm-diameter mycelial plug cut from the margin of 6-day-old PDA culture was applied to the marked areas on the upper leaf surface. The inoculated area was covered with moist cheese cloth and wrapped with Parafilm. Leaves treated with blank PDA plugs served as control. Leaves were enclosed in plastic bags to maintain moisture for the first 15 h post inoculation and cheese cloths were removed after 15 days. All cold-injured inoculated leaves showed symptoms of blight starting at 2 weeks after inoculation, and no symptoms appeared on the controls. On non-cold injured inoculated leaves, only one isolate caused symptoms (80% of all leaves). The fungus was re-isolated from diseased leaves. These results suggest that P. washingtonensis is able to cause foliar blight on Pacific madrone when leaves are subjected to cold stress. Increased disease severity on madrone observed in spring 2011 in Washington and Oregon may have been due to predisposition of foliage to extreme cold in November 2010 and February 2011. This fungus has previously been reported to cause a postharvest fruit rot disease on apple fruit and a canker and twig dieback disease of apple and crabapple trees in WA (1). To our knowledge, this is the first report of P. washingtonensis causing a leaf blight disease on Pacific madrone in North America. References: (1) C. L. Xiao et al. Mycologia 97:464, 2005. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.


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