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Abdel Azeiz A.Z.,MISR University for Science and Technology | Hanafi D.K.,Zewail City | Hasanein S.E.,Agriculture Genetic Engineering Research Institute AGERI
Natural Product Research | Year: 2015

Thirty actinomycete isolates were isolated from soil and tested against Candida albicans in vitro. The active isolate was identified by 16s-rRNA gene sequencing method as Streptomyces toxytricini. The antifungal compound was extracted with ethyl acetate followed by diethyl ether. Both HPLC and GC–MS analysis confirmed presence of one pure compound in the diethyl ether extract. The compound is a yellow liquid has a maximum absorbance at 240 nm in methanol. The chemical structure was elucidated by 1D and 2D-NMR and IR analyses. The elucidated molecular formula was C36H54O14. The compound is a polyacetal tricyclononane derivative, composed of a tricyclononane ring attached from the carbon atom number four with an oligo-acetal chain (six acetal groups in chain) and from the carbon atom number seven with a methoxy carbonyl benzene-1,3-dicarboxylic acid. The purposed name is: 4- {[tricycle(,3)non-8-yl] methoxy carbonyl benzene-1,3-dicarboxylic acid} (2,4,5,6,7,8,9 heptaoxa, 3-ethoxy, 5,6,7,9-tetramethyl unidecane). © 2015 Taylor & Francis

Momtaz O.A.,Agriculture Genetic Engineering Research Institute AGERI
GM crops & food | Year: 2014

We present an efficient method for the production of transgenic salt tolerant hexaploid wheat plants expressing the Arabidopsis AtNHX1 gene. Wheat mature zygotic embryos were isolated from two hexaploid bread wheat (Triticum aestivum) cultivars (namely: Gemmeiza 9 and Gemmeiza 10) and were transformed with the A. tumefaciens LBA4404 harboring the pBI-121 vector containing the AtNHX1 gene. Transgenic wheat lines that express the gus intron was obtained and used as control. The results confirmed that npt-II gene could be transmitted and expressed in the T2 following 3:1 Mendelian segregation while the control plant couldn't. The data indicate that, the AtNHX1 gene was integrated in a stable manner into the wheat genome and the corresponding transcripts were expressed. The transformation efficiency was 5.7 and 7.5% for cultivars Gemmeiza 10 and Gemmeiza 9, respectively. A greenhouse experiment was conducted to investigate the effect of AtNHX1 gene in wheat salt tolerance. The transgenic wheat lines could maintain high growth rate under salt stress condition (350 mM NaCl) while the control plant couldn't. The results confirmed that Na(+)/H(+) antiporter gene AtNHX1 increased salt tolerance by increasing Na(+) accumulation and keeping K+/Na(+) balance. Thus, transgenic plants showed high tolerance to salt stress and can be considered as a new genetic resource in breeding programs.

El-Gaied L.F.,Agriculture Genetic Engineering Research Institute AGERI
GM crops & food | Year: 2013

Bioregulators have a great effect on vital processes of plant growth and development. Known plant bioregulators include Naphthalene acetic acid (NAA), Indole-3-butyric acid (IBA) and Indole-3-acetic acid (IAA). Natural or synthetic plant bioregulators are organic compounds that affect the physiological processes in the plant, either to control some of these processes or to modify them. For example these bioregulators can affect the nature of the process, either by accelerating or decelerating plant growth, rates of maturation and also by altering the behavior of the plants or their products. Also, enhancement of important nutrients in human diet could be achieved by bioregulators.   This study uses the model crop plant Tomato (Lycopersicon esculentum). Tomato is affected by a group of bioregulators, this group contains compounds which are powerful antioxidants in vitro. The current study aims to find out the effect of some plant bioregulators (IAA, IBA and NAA) on tomato growth, total protein content and enzyme activities of ascorbate peroxidase (APX), superoxide dismutase (SOD) and catalase (CAT). This study also investigates the effect of the above mentioned bioregulators on the level of RNA expression for SOD, CAT and TPX1 genes. The analytical quantification of target gene expression showed the induced effect of NAA on SOD expression and reducing effect of the other bioregulators (IAA and IBA) on CAT and TPX1 expression. However, at the protein level, we found that IBA and IAA caused a minor effect on total protein content while a significant effect was recorded on the total protein level using NAA. Upon measuring the enzyme activity of ascorbate peroxidase and catalase, we found that both the exogenous NAA and IBA stimulated ascorbate peroxidase activity in tomato while there was no considerable difference detected in IAA treated plants. Also, there was no considerable difference detected in catalase activity of all bioregulator-treated plants compared with the control.

Gomaa O.M.,National Center for Radiation Research And Technology | Momtaz O.A.,Agriculture Genetic Engineering Research Institute AGERI | Kareem H.A.E.,National Center for Radiation Research And Technology | Fathy R.,National Center for Radiation Research And Technology
World Journal of Microbiology and Biotechnology | Year: 2011

Twenty-two local brown rot fungal isolates were obtained from 5 different environmental sources. Fourteen isolates were presumptively identified as Aspergillus sp. and eight as Penicillium sp. using mycelium and spore morphology. All the fungal isolates were screened for their ability to decolorize Isolan Red and colored waste water and to produce oxidase activity. Aspergillus isolate 2 was chosen for further study because it could decolorize both dyes and produce oxidase. A 400 bp fragment of the 18S rRNA gene from isolate 2 was analyzed by nucleotide sequence analysis. Blastn analysis of sequence data demonstrated 100% identity to Aspergillus sp. and isolate 2 was assigned the strain designation Aspergillus sp. EL-2 (Accession number: HM140797). EL-2 could remove up to 80% of Disperse Blue in waste water effluent within 48 h in submerged shake culture. The decolorization process was energy dependent, growth related, and required viable biomass. EL-2 was able to grow and decolorize waste water over a broad pH range. Addition of inducers and inhibitors of specific enzymes or families of enzymes demonstrated the involvement of phenol oxidase (laccase), cytochrome p-450 oxygenase and hydroxyl radicals in the decolorization process. The data also suggest that it may be practical to enhance decolorizing activity of Aspergillus sp. EL-2 through the metabolic control of fungal degradative pathways by altering media composition. © 2010 Springer Science+Business Media B.V.

El Awady M.A.M.,Taif University | El Awady M.A.M.,Cairo University | Essam El-Den K.M.,Taif University | Essam El-Den K.M.,Agriculture Genetic Engineering Research Institute AGERI | And 4 more authors.
Life Science Journal | Year: 2013

Grapevine fanleaf virus (GFLV) is the viral agent of one of the most severe diseases in vineyards worldwide. Survey of grapvine farms in Taif governorate, Mecca province, Kingdom of Saudi Arabia resulted in the detection of Grapevine plants (Vitis vinifera cv. Perelette) exhibited virus-like symptoms of the GFLV. Symptomatic samples were collected to confirm the viral infection through Double antibody sandwich-enzyme linked immunosorbent (DAS-ELISA) assay with Polyclonal antibodies (PAbs) specific to GFLV. Out of 48 tested samples, 43 samples representing 89.6% gave positive reactions with values ranged between 0.116 and 2,462 compared to values ranged between 0.003 and 0.085 of the 5 negative healthy samples. Grapevine plant with high viral titer showed typical fanleaf symptoms such as abnormal branching, double nodes, short Internodes with zigzag growth and fasciations, reduction of the leaves size with deformities and fan-leaf shape. These results were biologically confirmed following the detection of leaves malformation symptoms, mottling, ringspots and systemic chlorotic mosaic, in viral infected Nicotiana benthamiana, Phaseolus vulgaris and Cucurbita pepo, respectively. The inoculated plants developed symptoms 21 days post inoculation. The result obtained by ELISA was confirmed by western blot assay. To our knowledge, this is the first study performed in KSA dealing with the detection of grapevine viruses in naturally infected field-grown vines.

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