Asian Science Citation Index is committed to provide an authoritative, trusted and significant information by the coverage of the most important and influential journals to meet the needs of the global scientific community.  
ASCI Database
308-Lasani Town,
Sargodha Road,
Faisalabad, Pakistan
Fax: +92-41-8815544
Contact Via Web
Suggest a Journal
Articles by S. Riazuddin
Total Records ( 8 ) for S. Riazuddin
  Kausar Malik , Tariq Mahmood and S. Riazuddin
  120 Kda and 70 Kda protein in the larval midgut membrane of the lepidopteran Helicoverpa armigera identified as putative receptor for Bt Cry 1Ac delta-endotoxin .Receptor proteins have been purified by a combination of gel-filtration and anion exchange chromatography .In ligand-blotting experiment ,the purified protein has binding capacity with Cry 1Ac and Cry 1Ab but not to Cry 2A .N-terminal sequence obtained from the protein show no homology to already existing sequences .When assayed for amino-peptidase and alkaline phosphatase activities , purified receptors preparations were enriched 2.5 fold in amino-peptidase activity compare to Helicoverpa-armigera brush border membrane vesicles . The 70 Kda protein seems to be the part of 120 Kda receptor protein.
  Muhammad Ferhan , Zahoor Ahmed , S. Riazuddin , M.I. Rajoka and A. M. Khalid
  Phenol is one of the most common pollutants present in the environment. It enters into the soil and water through different pathways like cooking, plastic manufacturing, oil purification, pharmaceutical and timber industries. Good solubility of phenol in water and its high contents in industrial effluents testify to a high probability of phenol acting as a water pollutant. The industrial waste were collected from (AWT) Army Welfare Trust, Bhi Phareu at different locations and were analyzed spectrophotometrically for phenol concentration by aqueous method. The highest concentration of phenol was observed in the samples. In order to establish bioremedial process of phenolic compounds, bacteria were screened for their ability to utilize phenolic compounds. Pseudomonas putida strain CEMB 10124 degraded and utilized phenolic compounds as carbon and energy source. This strain could degrade 0.8 g l -1 phenol with in 40 h. The growth of bacteria was monitored spectrophotometrically at 600 nm. The disappearance of phenol was scanned between 220-320 nm. The decrease in phenol`s peak at 269 nm depicted the decrease of phenol in the growth medium and it was further analyzed by GC-ECD.
  Rizwana Anwar , Shahid Karim and S. Riazuddin
  Transgenic rice plants obtained through the incorporation of Bt cry1Ac gene. Initially putative transformants were screened for pesticidal activity against rice leaf folder larvae. Selected putative transformants showed a range of larval mortality from 20-100 percent to C. medinalis. The integration of the Bt cry gene was checked by Polymerase Chain Reaction (PCR), using primers 5` ACA GAA GAC CCT TCA ATA TC 3` and 3` GTT ACC GAG TGA AGA TGT AA 5` for amplification of a 656 bp fragment of DNA from the genomic DNA of putative transformants. Selection based on PCR and initial bioassays, two transgenic plants designated as, CAMB 1148 and CAMB 1150 were further confirmed for toxin expression by ELISA, Western blot analysis and comparative biotoxicity assay. ELISA and Western blot were performed with polyclonal antibody of Cry1Ac toxins that showed the presence of active ingredient of Bt toxin in both plants. Biotoxicity assays also reconfirmed the stability and activity of Cry toxins in both transgenic rice plants, eventually aiming for homozygosity with enhanced resistance to rice leaf folder.
  Kausar Malik and S. Riazuddin
  Proteins synthesized by the bacterium Bacillus thuringiensis are potent insecticides. When ingested by susceptible larvae they rapidly lyse epithelial cell lining of the midgut. The receptor protein in Helicoverpa armigera midgut appeared as single band on Non-SDS-PAGE but on SDS-PAGE. It resolved as two subunits (120kDa, 70kDa). We observed that the sugar N-acetyl galactosamine (GalNAc) showed no effect on binding of CryIAc toxin to receptor protein or in other words, toxin binding to receptor was not inhibited by GalNAc. This finding suggest that GalNAc might be not a component of a Cry1Ac toxin receptor Proteolysis of receptor proteins with trypsin and gut juice of Helicoverpa armigera showed that ~120Kda was digested while, ~70 kDa was trypsin and gut juice resistant and showed binding to CryIAc in ligand blots Proteolysis of receptor protein with pronase and proteinase-K showed digestion of ~120 kDa , ~70kDa and less than 40 kDa bands were appeared.
  M. A. Khan , R. Makhdoom , T. Husnain , M. Z. Saleem , K. Malik , Z. Latif , I. Altosaar and S. Riazuddin
  The possibility of using a monocot (maize) derived ubiquitin (Ubi) promoter to express a fully modified insecticidal cry gene of Bacillus thuringiensis in dicot plant, tobacco was studied. Tobacco (Nicotiana tabacum cv. xanthi) plants were transformed with Bt gene Cry-1Ac driven by Ubi promoter. Transgenic plants were confirmed for transformation, gene expression and insecticidal activity through PCR, GUS assays, Southern blot, Western blot analyses and insect bioassays. Bioassays with cry-1Ac transformed To and T1 transgenic plants showed high level of toxicity towards American bollworm (Heliothis armigera) giving 100% mortality of the larvae. This paper reported that monocot derived Ubi promoter expresses a Bt gene in a dicot plant in an effective manner to render the transformed plants highly resistant against Heliothis armigera.
  Syed Sarfraz Hussain , Tayyab Husnain and S. Riazuddin
  Successful cotton plant transformation depends on regeneration of plants from transformed cells. Recalcitrance of cotton to tissue culture has not only slowed the development of transgenic cotton but also narrowed its genetic base. Keeping this in view, an efficient in vitro plant regeneration system characterized by bulk, rapid and continuous production of somatic embryos using immature zygotic embryos, taken at various stages of development from ovules as explant has been developed in cotton. One of the drawbacks of using this is the requirement of large number of high quality immature zygotic embryos. To address this problem, we have developed a procedure that generates highly homogeneous populations of embryogenic calli by selectively propagating a small number of regeneration proficient calli derived from immature zygotic embryos. Stages showing the early cotyledon development cultured on modified Murashige and Skoog media proliferated intensely. Rapid callogenesis was observed from these immature zygotic embryos. To induce germination and plantlet growth, embryoids were placed on sterile processed cotton, saturated with Stewart and Hsu media. Upon development of roots and leaves, plantlets of 3-4 cms were potted in 1:1:1 mixture of sand, silt and peat moss under high humidity and further hardened under green house conditions. Using this system, we have been able to regenerate approximately 70% of healthy plantlets.
  Syed Sarfraz Hussain , Tayyab Husnain and S. Riazuddin
  Current approaches of cotton improvement include the use of genetic engineering, but progress in this area is limited because of notoriously recalcitrant nature of most elite cotton cultivars in tissue culture. A well-established regeneration system is desired for the improvement of cotton through genetic engineering. As it is reported that somatic embryos have been obtained from the regenerable lines of Coker 312 and Coker 315 but the problem with these varieties was the loss of embryogenic nature of callus with the passage of time. A procedure of recurrent somatic embryogenesis and twin embryo production in Gossypium hirsutum L Cv. Coker 312JS is being reported for the first time from the older somatic embryos. Calli were subcultured regularly. Embryogenic capacity was remained stable for more than two years. Similarly, twin embryo production was seen in second cycle of this system. This will help to propagate embryos for the development seed technology and gene transfer system.
  Syed Sarfraz Hussain , Tayyab Husnain and S. Riazuddin
  The study was undertaken to develop a culture technique permitting to grow cotton embryos from fertilization to germination with minimum of manipulation and maximum yield of viable plants. During the study, conditions were optimized for transfer of zygotic ovules after post anthesis and selection of media for the growth of ovules. Forty-eight hours post anthesis was selected as the most appropriate time since >50% of ovules were found alive, floating and developing. Also, ST medium was found suitable as it supported the growth very well and ovules continued to grow till the end of 10 weeks. This in-ovule technique has several advantages over culture of isolated embryos. The aseptic removal of 48 h old ovules from the ovaries was rapid and efficient and minimum damage was observed in this technique. No change of medium was needed during the entire culture period. This technique was used for the first time as a means of cotton transformation using Sonication assisted Agrobacterium mediated transformation (SAAT) method while a marker gene was used to transform cotton ovules.
Copyright   |   Desclaimer   |    Privacy Policy   |   Browsers   |   Accessibility