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1.
Larvae of the scarabaeid, Cyclocephala hirta, are major pests of turfgrass in California. A field test was conducted against third instars that included the following treatments: untreated control; chemical insecticide (bendiocarb); milky disease bacterium (Bacillus popilliae); and entomopathogenic nematodes (Steinernema feltiae and Heterorhabditis bacteriophora). There were no significant differences in population reduction among the treatments, but the larval population in all plots showed a dramatic decline. The C. hirta population had a natural occurrence of milky disease and blue disease caused by Rickettsiella popilliae. The prevalence of blue disease during the course of the study averaged < 10% but that of milky disease averaged about 20%. More significantly, the soil from all treatment plots when bioassayed for B. popilliae showed that 67–90% of the larvae became infected with this bacterium. None of the larvae became infected with the blue disease organism. We conclude that B. popilliae was occurring in epizootic proportions in our field tests and was a significant mortality factor in causing the decline of the C. hirta population. 相似文献
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Aina Hazimah Bahaman Azzmer Azzar Abdul Hamid Khairul Bariyyah Abd Halim Yilmaz Kaya Mohamed Faraj Edbeib 《Journal of biomolecular structure & dynamics》2020,38(14):4246-4258
Abstract Fungi of the Trichoderma species are valued industrial enzymes in support of the ‘zero-waste’ technology to convert agro-industrial biomass into valuable products, i.e. nanocellulose (NC). In this study, an in silico approach using substrate docking and molecular dynamic (MD) simulation was used to predict the order of which the multilayers of cellulosic polymers, i.e. lignin, hemicellulose and cellulose in oil palm leaves (OPL) are degraded by fungal enzymes, endocellulase and exocellulase. The study aimed to establish the catalytic tendencies of the enzymes to optimally degrade the cellulosic components of OPL for high yield production of NC. Energy minimized endocellulase and exocellulase models revealed satisfactory scores of PROCHECK (90.0% and 91.2%), Verify3D (97.23% and 98.85%) and ERRAT (95.24% and 91.00%) assessments. Active site prediction by blind docking, COACH meta-server and multiple sequence alignment indicated the catalytic triads for endocellulase and exocellulase were Ser116–His205–Glu249 and Ser382–Arg124–Asp385, respectively. Binding energy of endocellulase docked with hemicellulose (?6.0 ? kcal mol?1) was the most favourable followed by lignin (?5.6 ? kcal mol?1) and cellulose (?4.4 ? kcal mol?1). Exocellulase, contrarily, bonded favorably with lignin (?8.7 ? kcal mol?1), closely followed by cellulose (?8.5 ? kcal mol?1) and hemicellulose (?8.4 ? kcal mol?1). MDs simulations showed that interactions of complexes, endocellulase–hemicellulose and the exocellulase–cellulose being the most stable. Thus, the findings of the study successfully identified the specific actions of sugar-acting enzymes for NC production. Communicated by Ramaswamy H. Sarma 相似文献
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Mutations in C2orf37, Encoding a Nucleolar Protein, Cause Hypogonadism, Alopecia, Diabetes Mellitus, Mental Retardation, and Extrapyramidal Syndrome 下载免费PDF全文
Anas M. Alazami Amr Al-Saif Abdulaziz Al-Semari Saeed Bohlega Soumaya Zlitni Fatema Alzahrani Prashant Bavi Namik Kaya Dilek Colak Hanif Khalak Andy Baltus Borut Peterlin Sumita Danda Kailash P. Bhatia Susanne A. Schneider Nadia Sakati Christopher A. Walsh Futwan Al-Mohanna Brian Meyer Fowzan S. Alkuraya 《American journal of human genetics》2008,83(6):684-691
Hypogonadism, alopecia, diabetes mellitus, mental retardation, and extrapyramidal syndrome (also referenced as Woodhouse-Sakati syndrome) is a rare autosomal recessive multisystemic disorder. We have identified a founder mutation consisting of a single base-pair deletion in C2orf37 in eight families of Saudi origin. Three other loss-of-function mutations were subsequently discovered in patients of different ethnicities. The gene encodes a nucleolar protein of unknown function, and the cellular phenotype observed in patient lymphoblasts implicates a role for the nucleolus in the pathogenesis of this disease. Our findings expand the list of human disorders linked to the nucleolus and further highlight the developmental and/or maintenance functions of this organelle. 相似文献
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Discovery of potent carbonic anhydrase,acetylcholinesterase, and butyrylcholinesterase enzymes inhibitors: The new amides and thiazolidine‐4‐ones synthesized on an acetophenone base 下载免费PDF全文
Parham Taslimi Sabiya Osmanova İlhami Gulçin Sabira Sardarova Vagif Farzaliyev Afsun Sujayev Ruya Kaya Fatma Koc Sukru Beydemir Saleh H. Alwasel Omer Irfan Kufrevioglu 《Journal of biochemical and molecular toxicology》2017,31(9)
Compounds containing nitrogen and sulfur atoms can be widely used in various fields, including industry, medicine, biotechnology, and chemical technology. Among them, amides of acids and heterocyclic compounds have an important place. These amides and thiazolidine‐4‐ones showed good inhibitory action against butyrylcholinesterase (BChE), acetylcholinesterase (AChE), and human carbonic anhydrase isoforms. AChE exists at high concentrations in the brain and red blood cells. BChE is an important enzyme that is plentiful in the liver, and it is released into the blood in a soluble form. They were demonstrated to have effective inhibition profiles with Ki values of 23.76–102.75 nM against hCA I, 58.92–136.64 nM against hCA II, 1.40–12.86 nM against AChE, and 9.82–52.77 nM against BChE. On the other hand, acetazolamide showed Ki value of 482.63 ± 56.20 nM against hCA I, and 1019.60 ± 163.70 nM against hCA II. Additionally, Tacrine inhibited AChE and BChE, showing Ki values of 397.03 ± 31.66 and 210.21 ± 15.98 nM, respectively. 相似文献
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The development of an internal braconid parasitoid, Glyptapanteles militaris, is adversely affected when its host, Pseudaletia unipuncta, is infected with the Hawaiian strain of granulosis virus. A plasma-derived agent, isolated from virus-infected hosts, was shown to elicit developmental aberrations in the parasitoid similar to those observed in virus-infected hosts. This agent was isolated by ammonium sulfate precipitation, gel filtration, and anion exchange chromatography, and its molecular weight, established by gel filtration and SDS-polyacrylamide gel electrophoresis, was determined to be about 64,000. The dilution end point of the agent and some stability properties were also established. 相似文献
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Oily water treatment has attracted the attention of many researchers.The development of effective and cheap oil/water separation materials is urgent for treating this problem.Herein,inspired by superhydrophobic typical plant leaves such as lotus,red rose and marigold,superhydrophobic and superoleophilic copper mesh was fabricated by etching and then surface modification with 1-dodecanethiol (HS(CH2)11CH3).A rough silver layer is formed on the mesh surface after immersion.The obtained mesh surface exhibits superhydrophobicity and superoleophilicity and the static water contact angle was 153° ± 3°.In addition,the as-prepared copper mesh shows self-cleaning character with water and chemical stability.The as-prepared copper foam can easily remove the organic solvents either on water or underwater.We demonstrate that by using the as-prepared mesh,oils can be absorbed and separated,and that high separation efficiencies of larger than 92% are retained for various oils.Thus,such superhydrophobic and superoleophilic copper mesh is a very promising material for the application of oil spill cleanup and industrial oily wastewater treatment. 相似文献
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A total of 270 soil samples from 30 different habitats in 10 geographic regions of California were evaluated for the presence of rhabditid entomopathogenic nematodes. Nematodes were isolated from 26.3% of the samples. The recovered isolates were identified as Steinernema carpocapsae, S. feltiae, S. kraussei, S. longicaudum, S. oregonense, Heterorhabditis marelatus and H.bacteriophora. Among the steinernematids, S. kraussei and S. feltiae were the most commonly encountered species, generally occurring in acidic soils high in organic matter. Among the heterorhabditids, H. bacteriophora was isolated along the southern coast, whereas H. marelatus was recovered along the northern coast of California. Steinernematids were recovered from coniferous forests, oak woodlands and grasslands whereas heterorhabditids were isolated from coastal marshes. 相似文献