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101.
Vector control is one of the major global strategies for control of malaria. However, the major obstacle for vector control is the development of multiple resistances to organochlorine, organophosphorus insecticides and pyrethroids that are currently being used in public health for spraying and in bednets. Salivary glands of vectors are the first target organ for human-vector contact during biting and parasite-vector contact prior to parasite development in the mosquito midguts. The salivary glands secrete anti-haemostatic, anti-inflammatory biologically active molecules to facilitate blood feeding from the host and also inadvertently inject malaria parasites into the vertebrate host. The Anopheles stephensi mosquito, an urban vector of malaria to both human and rodent species has been identified as a reference laboratory model to study mosquito—parasite interactions. In this study, we adopted a conventional proteomic approach of 2D-electrophoresis coupled with MALDI-TOF mass spectrometry and bioinformatics to identify putative differentially expressed annotated functional salivary proteins between An. stephensi susceptible and multiresistant strains with same genetic background. Our results show 2D gel profile and MALDI-TOF comparisons that identified 31 differentially expressed putative modulated proteins in deltamethrin/DDT resistant strains of An. stephensi. Among these 15 proteins were found to be upregulated and 16 proteins were downregulated. Our studies interpret that An. stephensi (multiresistant) caused an upregulated expression of proteins and enzymes like cytochrome 450, short chain dehyrdogenase reductase, phosphodiesterase etc that may have an impact in insecticide resistance and xenobiotic detoxification. Our study elucidates a proteomic response of salivary glands differentially regulated proteins in response to insecticide resistance development which include structural, redox and regulatory enzymes of several pathways. These identified proteins may play a role in regulating mosquito biting behavior patterns and may have implications in the development of malaria parasites in resistant mosquitoes during parasite transmission.  相似文献   
102.
Flowering phenology is very sensitive to climate and with increasing global warming the flowering time of plants is shifting to earlier or later dates. Changes in flowering times may affect species reproductive success, associated phenological events, species synchrony, and community composition. Long‐term data on phenological events can provide key insights into the impacts of climate on phenology. For Australia, however, limited data availability restricts our ability to assess the impacts of climate change on plant phenology. To address this limitation other data sources must be explored such as the use of herbarium specimens to conduct studies on flowering phenology. This study uses herbarium specimens for investigating the flowering phenology of five dominant and commercially important Eucalyptus species of south‐eastern Australia and the consequences of climate variability and change on flowering phenology. Relative to precipitation and air humidity, mean temperature of the preceding 3 months was the most influential factor on the flowering time for all species. In response to a temperature increment of 1°C, a shift in the timing of flowering of 14.1–14.9 days was predicted for E. microcarpa and E. tricarpa while delays in flowering of 11.3–15.5 days were found for E. obliqua, E. radiata and E. polyanthemos. Eucalyptus polyanthemos exhibited the greatest sensitivity to climatic variables. The study demonstrates that herbarium data can be used to detect climatic signals on flowering phenology for species with a long flowering duration, such as eucalypts. The robust relationship identified between temperature and flowering phenology indicates that shifts in flowering times will occur under predicted climate change which may affect reproductive success, fitness, plant communities and ecosystems.  相似文献   
103.
104.
Receptor-based QSAR approaches can enumerate the energetic contributions of amino acid residues toward ligand binding only when experimental binding affinity is associated. The structural data of protein-ligand complexes are witnessing a tremendous growth in the Protein Data Bank deposited with a few entries on binding affinity. We present here a new approach to compute the E nergetic CONT ributions of A mino acid residues and its possible C ross-T alk (ECONTACT) to study ligand binding using per-residue energy decomposition, molecular dynamics simulations and rescoring method without the need for experimental binding affinity. This approach recognizes potential cross-talks among amino acid residues imparting a nonadditive effect to the binding affinity with evidence of correlative motions in the dynamics simulations. The protein-ligand interaction energies deduced from multiple structures are decomposed into per-residue energy terms, which are employed as variables to principal component analysis and generated cross-terms. Out of 16 cross-talks derived from eight datasets of protein-ligand systems, the ECONTACT approach is able to associate 10 potential cross-talks with site-directed mutagenesis, free energy, and dynamics simulations data strongly. We modeled these key determinants of ligand binding using joint probability density function (jPDF) to identify cross-talks in protein structures. The top two cross-talks identified by ECONTACT approach corroborated with the experimental findings. Furthermore, virtual screening exercise using ECONTACT models better discriminated known inhibitors from decoy molecules. This approach proposes the jPDF metric to estimate the probability of observing cross-talks in any protein-ligand complex. The source code and related resources to perform ECONTACT modeling is available freely at https://www.gujaratuniversity.ac.in/econtact /.  相似文献   
105.
An efficient in vitro propagation protocol for Habenaria edgeworthii Hook. f. ex. Collett using seed-derived callus was established. The maximum seed germination was observed in Murashige and Skoog (MS) medium supplemented with 1.0 μM α-naphthalene acetic acid (NAA). Induction of callus was achieved on full and ½-strength MS medium supplemented with 1.0 μM NAA. The highest number of shoot (11.9 shoots/explant) was achieved in MS medium supplemented with 0.1 μM 6-benzyladenine (BA) and 0.01 μM NAA. Further, elongated shoots when transferred to ½-strength MS rooting medium with different auxin concentrations induced roots (41.6–83.3%) and tubers (0–20.8%); however, a maximum of 87.5% rooting was achieved in a plant growth regulator (PGR)-free MS medium. Rooted shoots (plantlets) when transferred to a mixture of soil:sand:perlite (1:1:1 ratio) resulted in 68% survival. Inter-simple sequence repeats (ISSR) markers confirmed the genetic stability among regenerated plants. The phytochemical analysis of tissue culture-raised tubers showed higher phenolic content than wild tuber. The regeneration protocol developed in this study provides a basis for germplasm conservation and harnessing the total phenol and phenolic compounds of H. edgeworthii. Further, the methods can open avenues for application in other Orchidaceous plants of the Indian Himalayan region.  相似文献   
106.
Alkalibacillus haloalkaliphilus C-5 is a haloalkaliphilic bacterium that was isolated from a soil sample from the salty Sambhar Lake, Rajasthan, India. The organism is capable of alkaline protease production under conditions of pH 10 and 10% (wt/vol) salt. We sequenced and have reported the whole genome of Alkalibacillus haloalkaliphilus C-5, of Indian origin, for the first time.  相似文献   
107.
Caffeoyl coenzyme A O-methyltransferase (CCoAOMT) is an important enzyme that participates in lignin biosynthesis especially in the formation of cell wall ferulic esters of plants. It plays a pivotal role in the methylation of the 3-hydroxyl group of caffeoyl CoA. Two cDNA clones that code CCoAOMT were isolated earlier from subabul and in the present study; 3D models of CCoAOMT1 and CCoAOMT2 enzymes were built using the MODELLER7v7 software to find out the substrate binding sites. These two proteins differed only in two amino acids and may have little or no functional redundancy. Refined models of the proteins were obtained after energy minimization and molecular dynamics in a solvated water layer. The models were further assessed by PROCHECK, WHATCHECK, Verify_3D and ERRAT programs and the results indicated that these models are reliable for further active site and docking analysis. The refined models showed that the two proteins have 9 and 10 α-helices, 6 and 7 β-sheets respectively. The models were used for docking the substrates CoA, SAM, SAH, caffeoyl CoA, feruloyl CoA, 5-hydroxy feruloyl CoA and sinapyl CoA which showed that CoA and caffeoyl CoA are binding with high affinity with the enzymes in the presence and absence of SAM. It appears therefore that caffeoyl CoA is the substrate for both the isoenzymes. The results also indicated that CoA and caffeoyl CoA are binding with higher affinity to CCoAOMT2 than CCoAOMT1. Therefore, CCoAOMT2 conformation is thought to be the active form that exists in subabul. Docking studies indicated that conserved active site residues Met58, Thr60, Val63, Glu82, Gly84, Ser90, Asp160, Asp162, Thr169, Asn191 and Arg203 in CCoAOMT1 and CCoAOMT2 enzymes create the positive charge to balance the negatively charged caffeoyl CoA and play an important role in maintaining a functional conformation and are directly involved in donor-substrate binding.  相似文献   
108.
Summary Immature seeds of Garcinia indica Choiss, were exeised from immature fruits and cultured on Lloyd and McCown (1980), woody plant medium (WPM) with different combinations of auxins and cytokinins. Somatic embryos were obtained on the media supplemented with 6-benzy laminopurine (BA; 2.2–22.1 μM) alone or in combination with α-naphthalene acetic acid (NAA; 2.6 μM) with 80% frequency within a period of 2–3 wk. Subculture of embryos on medium containing BA (16.0 μM) supplemented with indole-3-acetic acid (IAA: 2.8–5.7 μM) and/or kinetin (4.6 μM) gave rise to clusters of secondary somatic embryos along with maturation of primary embryos. In subsequent subculture on hormone-free half-strength WPM, the embryo clusters germinated with an increase in the number of secondary somatic embryos. About 70% of somatic embryos germinated into complete plantlets, which were successfully established under greenhouse conditions.  相似文献   
109.
Only few enzymes from haloalkaliphiles are biochemically characterized for their kinetic behaviour and stability. In view of this realization, an alkaline protease from Bacillus sp. AH-6, displaying salt-dependent resistance against chemical denaturation by Urea and Guanidium hydrochloride was investigated for denaturation and in vitro protein folding. The crude enzyme was highly resistant against urea (8 M) denaturation up to 72 h; however, on purification, it turned sensitive and got denatured within 2 h. Interestingly, the purified enzyme regained the resistance in the presence of NaCl. Effective refolding of the purified enzyme was achieved with glycerol; however, other approaches such as lower protein concentrations, rapid dilution and slow removal of the denaturant did not further add to refolding. The results are important from the viewpoint that only few enzymes from haloalkaliphilic bacteria are characterized. Since the resistance against chemical denaturation is a rare phenomenon, the findings would enrich the knowledge on protein stability and denaturation. Besides, such biocatalysts would definitely have novel applications under harsh chemical environments.  相似文献   
110.
Hepatitis C virus (HCV) NS5B RNA polymerase is crucial for replicating the HCV RNA genome and is an attractive target for developing anti-HCV drugs. A novel series of 2,3-diaryl-1,3-thiazolidin-4-one derivatives were evaluated for their ability to inhibit HCV NS5B. Of this series, compounds 4c, 5b, 5c and 6 emerged as more potent, displaying over 95% inhibition of NS5B RNA polymerase activity in vitro. The two most active compounds 4c and 5c exhibited an IC(50) of 31.9 microM and 32.2 microM, respectively, against HCV NS5B.  相似文献   
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