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Assaeedi A.S.A.,University of Umm Al - Qura | Osman G.E.H.,University of Umm Al - Qura | Osman G.E.H.,Agricultural Genetic Engineering Research Institute | Abulreesh H.H.,University of Umm Al - Qura
Australian Journal of Crop Science | Year: 2011

Pest control in Saudi Arabia is entirely relied on the application of chemical agents. Little information is known about the natural presence of Bacillus thuringiensis species that possess insecticidal activity in the environment of Saudi Arabia. It would be of interest to search for native species of toxic Bt strains that can be used in pest control management. Thus the aim of this study was to investigate the natural presence of Bacillus thuringiensis species that are toxic to pests in the environment of Makkah Province, western Saudi Arabia. A total of 100 soil samples and five dead larvae of Spodoptera littoralis (Lepidoptera) were examined for the presence of Bacillus thuringiensis. The bacterium was isolated by acetate-selective enrichment and plating. Identification of isolates was performed by microscopic examination, analysis of parasporal inclusions protein profiles by SDS-PAGE, toxicity assay, analysis of 16S rDNA genes and DNA sequencing for PCR products. The confirmed Bacillus thuringiensis isolates, eight in total, were recovered from 5% of soil samples and from 60% of dead larvae. These isolates exhibited strong activity against 1 st instar larvae of S. littoralis. Although Bacillus thuringiensis was not found to be abundant in soil habitats in Makkah Province, the results suggest that the bacterium is part of the indigenous microflora of the area we have explored. This is the first report of the natural presence of lepidopteran-toxic strains of Bacillus thuringiensis in the environment of western Saudi Arabia, particularly in Makkah Province. Source

Maaty W.S.,Agricultural Genetic Engineering Research Institute | Maaty W.S.,University of Kansas | Weis D.D.,University of Kansas
Journal of the American Chemical Society | Year: 2016

There is considerable interest in the discovery of peptide ligands that bind to protein targets. Discovery of such ligands is usually approached by screening large peptide libraries. However, the individual peptides must be tethered to a tag that preserves their individual identities (e.g., phage display or one-bead one-compound). To overcome this limitation, we have developed a method for screening libraries of label-free peptides for binding to a protein target in solution as a single batch. The screening is based on decreased amide hydrogen exchange by peptides that bind to the target. Hydrogen exchange is measured by mass spectrometry. We demonstrate the approach using a peptide library derived from the Escherichia coli proteome that contained 6664 identifiable features. The library was spiked separately with a peptide spanning the calmodulin binding domain of endothelial nitric oxide synthase (eNOS, 494-513) and a peptide spanning the N-terminal 20 residues of bovine ribonuclease A (S peptide). Human calmodulin and bovine ribonuclease S (RNase S) were screened against the library. Using a novel data analysis workflow, we identified the eNOS peptide as the only calmodulin binding peptide and S peptide as the only ribonuclease S binding peptide in the library. © 2016 American Chemical Society. Source

Ibrahim A.S.,Cairo University | El-Shihy O.M.,Cairo University | Fahmy A.H.,Agricultural Genetic Engineering Research Institute
American-Eurasian Journal of Sustainable Agriculture | Year: 2010

Plant engineering via gene transfer technology Gene Revolution is a powerful technique for direct improvement of commercial crops by developing of novel plants expressing a set of valuable characters. Although, the production of stable fertile transgenic cell lines expressing target genes from commercial varieties remains a major barrier, in particular with cereal crops. High regeneration capacity from commercial barley varieties is a fundamental requirement for establishing efficient genetic transformation protocol of this important cereal crop. Here, we provide a robust, reliable and reproducible protocol for regeneration via embryogenesis and Agrobacterium-mediated transformation of two elite Egyptian barley cultivars Giza 123 (hulled) and Giza 130 (hull-less). The results of regeneration frequencies were exceeded 80% for both cultivars Giza 123 and Giza 130. These results of high regeneration efficiency proved that this protocol is less genotype-dependent plant regeneration system and was enabled us to attain high frequencies of transgenic plants. In total sixty three transgenic cell lines of Giza 123 cultivar with 179 positive plants expressing uidA and hpt genes resulted from eight independent experiments using 1210 explants (half immature embryos) with transformation frequencies % ranging between 6.41% and 23.77% with an average value 14.79%. In Comparison to 54 transgenic cell lines of Giza 130 with 131 positive plants resulted from eight independent experiments using 1268 explants with transformation frequencies % ranging between 3.73% and 17.57% with an average value 10.33%. Results of molecular analysis confirmed the generation of self-fertile transgenic plants of commercial barley cultivars; Giza 123 and Giza 130. The obtained results in this study confirm the efficiency of the developed protocol for barley transformation which represents a millstone will sustain our strategy to improve the nutritional value of the grains of these two elite cultivars through metabolic engineering technology. Moreover, these results will pave the way for further development of transgenic plants of other commercial barley cultivars and other cereal crops such as wheat, maize, rice and sorghum. Source

Sawan Z.M.,Cotton Research Institute | Fahmy A.H.,Agricultural Genetic Engineering Research Institute | Yousef S.E.,Seed Research Unit
Archives of Agronomy and Soil Science | Year: 2011

Conditions prevailing during seed formation can affect the quality of seed produced, and hence crop establishment in the next growing season. Two field experiments were conducted to investigate the effect of potassium, zinc and phosphorus on seed yield, seed viability, and seedling vigor of cotton cv. Giza 86. Fertilizer applications occurred as follows: two rates of potassium (0.0 and 47 kg ha-1 K) soil-applied in bands three weeks after sowing; two rates of chelated zinc (0.0 and 58 g ha-1 Zn) foliar sprayed twice, at 70 and 85 days after sowing (during square initiation and boll setting stage), and, four rates of phosphorus foliar sprayed twice as a solution of calcium super phosphate (0.0, 576, 1152 and 1728 g ha-1 P), at 80 and 95 days after sowing. Dry matter yield, total chlorophyll concentration, K, Zn and P uptake plant-1, seed yield ha71, seed weight, seed viability, seedling vigor, and cool germination test performance increased with the addition of K, Zn, and P. Band application of K at 47 kg ha-1 and foliar application of relatively low rates of Zn (58 g ha-1) and P (1728 g ha-1) improved cotton-seed yield and quality. © 2011 Taylor & Francis. Source

Al-Shafeay A.F.,Agricultural Genetic Engineering Research Institute
GM crops | Year: 2011

Sesame (Sesamum indicum L.) is an important oil crop in many tropical and sub-tropical regions of the world, yet has received little attention in applying modern biotechnology in its improvement due to regeneration and transformation difficulties. Here within, we report the successful production of transgenic fertile plants of sesame (cv Sohag 1), after screening several cultivars. Agrobacterium tumefaciens- carrying the pBI121 plasmid {neomycin phosphotransferase gene (NPTII) and a β-glucuronidase gene (GUS)} was used in all experiments. Recovery of transgenic sesame shoots was achieved using shoot induction medium (Murashige and Skoog MS basal salt mixture + Gamborg's B5 vitamins + 2.0 mg/l BA + 1.0 mg/l IAA + 5.0 mg/l AgNO3 + 30.0 g/l sucrose + 7.0 g/l agar + 200 mg/l cefotaxime and 25 mg/l kanamycin) and shoots were rooted on MS medium + B5 vitamins + 1.0 mg/l IAA + 10.0 g/l sucrose and 7.0 g/l agar. Rooted shoots were transplanted into soil and grown to maturity in greenhouse. Incorporation and expression of the GUS gene into T0 sesame plants was confirmed using polymerase chain reaction (PCR), reverse transcriptase-PCR (RT-PCR) and GUS histochemical assay. Several factors were found to be important for regeneration and transformation in sesame. The most effective were plant genotype and the addition of AgNO3 for successful recovery of sesame shoots. Co-cultivation time and optical density of the Agrobacterium were also critical for sesame transformation. This work is an attempt to open the door for further genetic improvement of sesame using important agronomic traits. Source

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