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41.
Many wild and managed bee pollinators have experienced population declines over the past several decades, and molecular and population genetic tools have been valuable in understanding conservation threats across the bee tree of life. Emerging genomic tools have the potential to improve classical applications of conservation genetics, such as assessing species status, and quantifying genetic diversity, gene flow and effective population sizes. Genomic tools can also revolutionize novel research in bee conservation and management, including the identification of loci underlying adaptive and economically desirable traits, such as those involved in disease susceptibility, responses to multiple environmental stressors, and even discovering and understanding the hidden diversity of beneficial microorganisms associated with bees. In this perspective, we provide a survey of some of the ways genomic tools can be applied to bee conservation to bridge the gap between basic and applied genomics research. 相似文献
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43.
Brock A. Harpur Anna Chernyshova Arash Soltani Nadejda Tsvetkov Mohammad Mahjoorighasrodashti Zhixing Xu Amro Zayed 《PloS one》2014,9(8)
Many animals have individual and social mechanisms for combating pathogens. Animals may exhibit short-term physiological tradeoffs between social and individual immunity because the latter is often energetically costly. Genetic tradeoffs between these two traits can also occur if mutations that enhance social immunity diminish individual immunity, or vice versa. Physiological tradeoffs between individual and social immunity have been previously documented in insects, but there has been no study of genetic tradeoffs involving these traits. There is strong evidence that some genes influence both innate immunity and behaviour in social insects – a prerequisite for genetic tradeoffs. Quantifying genetic tradeoffs is critical for understanding the evolution of immunity in social insects and for devising effective strategies for breeding disease-resistant pollinator populations. We conducted two experiments to test the hypothesis of a genetic tradeoff between social and individual immunity in the honey bee, Apis mellifera. First, we estimated the relative contribution of genetics to individual variation in innate immunity of honey bee workers, as only heritable traits can experience genetic tradeoffs. Second, we examined if worker bees with hygienic sisters have reduced individual innate immune response. We genotyped several hundred workers from two colonies and found that patriline genotype does not significantly influence the antimicrobial activity of a worker’s hemolymph. Further, we did not find a negative correlation between hygienic behaviour and the average antimicrobial activity of a worker’s hemolymph across 30 honey bee colonies. Taken together, our work indicates no genetic tradeoffs between hygienic behaviour and innate immunity in honey bees. Our work suggests that using artificial selection to increase hygienic behaviour of honey bee colonies is not expected to concurrently compromise individual innate immunity of worker bees. 相似文献
44.
Salman A. Khan Abdullah M. Asiri Khalid A. Alamry Samy A. El-Daly Mohie A. M. Zayed 《Russian Journal of Bioorganic Chemistry》2013,39(3):312-317
Chalcone derivatives have been synthesized by reaction of 1-(2,5-dimethyl-furan-3-yl)-ethanone with corresponding active aldehyde in ethanolic NaOH in microwave oven. The structure of these compounds was established by elemental analysis, IR, 1H NMR, 13C NMR, and EI-MS spectral analysis. The anti-bacterial activity of these compounds was first tested in vitro by the disc diffusion assay against two Gram-positive and two Gram-negative bacteria, and then the minimum inhibitory concentration (MIC) was determined with the reference of standard drug chloramphenicol. The results showed that pyrazol containing chalcone (compound 8) inhibited both types of bacteria (Gram-positive and Gram-negative) better than chloramphenicol. 相似文献
45.
G Zayed 《Journal of industrial microbiology & biotechnology》1997,19(1):39-42
Among three esters of p-hydroxybenzoate, n-butyl p-hydroxybenzoate was selected as the best antimicrobial substance. Molasses medium sterilized by this ester was used as
a substrate for ethanol production. n-Butyl p-hydroxybenzoate (0.15% w/v) completely inhibited the growth of free yeast cell inoculum, Ca-alginate immobilized yeast
inoculum and bacterial contaminants. Immobilization of the yeast cell inoculum in Ca-alginate with castor oil (6% v/v) offered
a yeast cell protection against the inhibitory effect of n-butyl p-hydroxybenzoate. The presence of castor oil in this immobilization system did not affect the metabolic activity of the yeast
in beads compared to the cells immobilized without castor oil. The yeast cell beads in this system completely utilized up
to 25% molasses sugar with an ethanol yield of 10.58%, equal to 83% of its theoretical value. The beads were stable and
could be used successfully for seven cycles of batch fermentation. The optimum fermentation temperature using this system
was 35°C.
Received 21 January 1997/ Accepted in revised form 05 May 1997 相似文献
46.
Growth Stage –Based Phenotypic Analysis of Arabidopsis: A Model for High Throughput Functional Genomics in Plants 下载免费PDF全文
Douglas C. Boyes Adel M. Zayed Robert Ascenzi Amy J. McCaskill Neil E. Hoffman Keith R. Davis Jrn Grlach 《The Plant cell》2001,13(7):1499-1510
With the completion of the Arabidopsis genome sequencing project, the next major challenge is the large-scale determination of gene function. As a model organism for agricultural biotechnology, Arabidopsis presents the opportunity to provide key insights into the way that gene function can affect commercial crop production. In an attempt to aid in the rapid discovery of gene function, we have established a high throughput phenotypic analysis process based on a series of defined growth stages that serve both as developmental landmarks and as triggers for the collection of morphological data. The data collection process has been divided into two complementary platforms to ensure the capture of detailed data describing Arabidopsis growth and development over the entire life of the plant. The first platform characterizes early seedling growth on vertical plates for a period of 2 weeks. The second platform consists of an extensive set of measurements from plants grown on soil for a period of approximately 2 months. When combined with parallel processes for metabolic and gene expression profiling, these platforms constitute a core technology in the high throughput determination of gene function. We present here analyses of the development of wild-type Columbia (Col-0) plants and selected mutants to illustrate a framework methodology that can be used to identify and interpret phenotypic differences in plants resulting from genetic variation and/or environmental stress. 相似文献
47.
Khalafalla Malik M. Zayed Nahed F. A. Amer Asem A. Soliman Ali A. Zaineldin Amr I. Gewaily Mahmoud S. Hassan Aziza M. Van Doan Hien Tapingkae Wanaporn Dawood Mahmoud A. O. 《Probiotics and antimicrobial proteins》2022,14(1):189-203
Probiotics and Antimicrobial Proteins - Dietary Lactobacillus acidophilus ATCC 4356 was used to relieve the impacts of aflatoxin B1 toxicity on the performances of Liza ramada. The control diet was... 相似文献
48.
The population genetics of a solitary oligolectic sweat bee, Lasioglossum (Sphecodogastra) oenotherae (Hymenoptera: Halictidae) 总被引:1,自引:0,他引:1
Strong evidence exists for global declines in pollinator populations. Data on the population genetics of solitary bees, especially diet specialists, are generally lacking. We studied the population genetics of the oligolectic bee Lasioglossum oenotherae, a specialist on the pollen of evening primrose (Onagraceae), by genotyping 455 females from 15 populations across the bee's North American range at six hyper-variable microsatellite loci. We found significant levels of genetic differentiation between populations, even at small geographic scales, as well as significant patterns of isolation by distance. However, using multilocus genotype assignment tests, we detected 11 first-generation migrants indicating that L. oenotherae's sub-populations are experiencing ongoing gene flow. Southern populations of L. oenotherae were significantly more likely to deviate from Hardy-Weinberg equilibrium and from genotypic equilibrium, suggesting regional differences in gene flow and/or drift and inbreeding. Short-term N(e) estimated using temporal changes in allele frequencies in several populations ranged from approximately 223 to 960. We discuss our findings in terms of the conservation genetics of specialist pollinators, a group of considerable ecological importance. 相似文献
49.
50.
Zayed ME 《Communications in agricultural and applied biological sciences》2004,69(4):779-788
Microorganisms can be identified in many ways. Conventional methods rely on the expression of certain properties that are usually mediated directly by enzyme activity. Extension of this approach to include numerical identification or automated systems to analyze results often strengthens conclusions. Identification of bacterial species using morphological characters and biochemical tests is often difficult and time consuming. Immunodiagnostic and nucleotide hybridization techniques have improved sensitivity, specify, precision, and ease of testing. Chemotaxonomy is also precise and can result in the definition of highly discriminatory properties. Cellular Fatty Acids (CFA) analyses fall into this category. One of the most convenient methods for the identification of fatty acids in bacterial cells is by gas-liquid chromatography of their methyl esters prepared from phospholipids, total lipids, or other lipid fractions. Two bacterial strains from Bahar Yossof. Al-Fayiurn governorates, Egypt tentatively identified as a species of pseudomonas by virtue of its physiological and biochemical characteristics. Confirmation of this identification was carried out using fatty acids profile analysis. 相似文献