Iranian Journal of Biotechnology
Volume:7 Issue: 1, Winter 2009

High levels of regulated oncogen-alpha (GRO-a) expression have been observed in the liver. GRO-a stimulates proliferation of epithelial cells and induction of rolling and extravascular migration of neutrophils and mononuclear cells. Given the above observations, this chemokine was chosen to be analyzed in freshly isolated and cultured hepatocytes. In this study, hepatocytes (2×106 cell/ml) were isolated from male Sprague Dawley rat liver and cultured on plates that were pre-coated with collagen type-I matrix. The western and northern blot analyses were employed to detect GRO-a at the protein and mRNA levels in freshly isolated and cultured hepatocytes in response to isolation and heat shock stresses. GRO-a was shown to be expressed by isolated rat hepatocytes immediately after isolation and early culture and decreased with time. mRNA was also expressed in freshly isolated cells (0 h) and did not decrease after 48h of culture and further time points (P<0.01). These results also demonstrated that expression of GRO-a by hepatocytes increased in response to heat shock at different time points in comparison with the control (P<0.01). These results demonstrated that the isolation and heat shock stresses induced the expression of GRO-a in hepatocytes in a time-dependent manner. Thus, it seems that hepatocytes mimic the experiences that the liver encounters after injury in vivo. In such a situation, liver produces stress related agents like chemokines to overcome injurious conditions. Keywords: Hepatocyte; GRO-a; Chemokine; Heat shock

This paper describes optimization method that combines the Plackett-Burman design, a factorial design and the response surface method, which were used to optimize the medium for the production of L-asparaginase by Serratia marcescens SB08. Four medium factors, from out of 11 medium factors, were screened by Plackett-Burman design experiments and subsequent optimization process to find out the optimum values of the selected parameters using central composite design was performed. Sucrose, peptone, KH2PO4 and incubation time were found to be the best medium factors for the optimization of L-asparaginase production and central composite design experiments indicated the optimal concentrations of sucrose 12.50 g/l, peptone 4.5 g/l, KH2PO4 4.0 g/l and incubation time 51h. The combined optimization method described here is the effective for screening medium factors as well as determining their optimum levels for the production of L-asparaginase by Serratia marcescens SB08. Keywords: Serratia marcescens SB08; L-asparaginase; PBD; CCD

In this research, an experimental study to evaluate nutrient removal from synthetic wastewater by a lab-scale moving bed biofilm process was investigated. Also, kinetic analysis of the process with regard to phosphorus and nitrogen removal was studied with different mathematical models. For nutrient removal, the moving bed biofilm process was applied in series with anaerobic, anoxic and aerobic units in four separate reactors that were operated continuously at different loading rates of phosphorus and nitrogen and different hydraulic retention times. Under optimum conditions, almost complete nitrification with an average ammonium removal efficiency of 99.72% occurred in the aerobic reactor. In the aerobic reactor, the average specific nitrification rate was 1.92 g NOx-N (NOx-N=NO2-N +NO3-N) produced/kg volatile suspended solids. hour (VSS.h). Denitrification rate increased with increasing NOx-N loading in the second anoxic reactor. The aerobic phosphate removal rate showed good correlation with the anaerobic phosphate release rate. Under optimum conditions, the average total nitrogen and phosphorus removal efficiencies were 80.9% and 95.8%, respectively. As a result of the moving bed biofilm process (MBBR) kinetic analysis, the Stover-Kincannon model was chosen for modeling studies and experimental data analysis. The Stover-Kincannon model gave high correlation coefficients for phosphorus and nitrogen removal, which were 0.9862 and 0.986, respectively. Therefore, this model could be used in predicting the behavior or design of the moving bed biofilm process. Stover-Kincannon model During optimum conditions, close to complete nitrification an average ammonium removal efficiency of 99.72% occurred in the aerobic reactor. In the aerobic reactor, the average specific nitrification rate was 1.92 g NOx-N produced/kg VSS.h. Denitrification rate has increased with increasing NOx-N loading in the second anoxic reactor. The aerobic phosphate removal rate showed a good correlation to the anaerobic phosphate release rate. In optimum conditions, the average total nitrogen and phosphorus removal efficiencies were 80.9% and 95.8%, respectively. As a result of the MBBR kinetic analysis, Stover-Kincannon model has been chosen for modeling studies and experimental data analysis. Stover-Kincannon model gave high correlation coefficients for phosphorus and nitrogen removal, which were 0.9862 and 0.986, respectively. Therefore, this model could be used in predicting the behavior or design of the moving bed biofilm process.

The domesticated silkworm, Bombyx mori, is of high commercial importance as a silk producer and is also widely used for implementation of basic and applied research. It is important to understand its genome organization using molecular markers for genetic studies and for breeding purposes. In this study, a genetic linkage map using 204 amplified fragment length polymorphism (AFLP) markers was developed. Twenty PstI/TaqI primer combinations were used to genotype 78 progenies from an F2 population of the P107×Khorasan Lemon cross. Each primer combination generated an average of 10.2 AFLP markers qualified for linkage mapping. All the 204 AFLP markers were assigned to 12 linkage groups at the Logarithm of Odds (LOD) threshold of 2. The number of markers in the linkage groups ranged from 2 to 53. There were seven major linkage groups with 13-53 markers and five small linkage groups with 2-6 markers. The 12 linkage groups varied in length from 12.3 to 938.4 cM and the total length of linkage map was 4262 cM, giving an average marker resolution of 20.89 cM. This study presents the preliminary step for further marker-assisted research on silkworm, including Quantitative Trait Loci (QTL) and introgression analyses.

Micropropagated plantlets derived from three different grape rootstock genotypes namely, Dogridge (Vitis champini), SO4 (V. berlandieri×V. rupestris) and ARI-H-144 (V. vinifera×V. labrusca) were subjected to randomly amplified polymorphic DNA (RAPD) and inter simple sequence repeats (ISSR) analyses in order to evaluate their genetic stability and/or detect likely existing variations among in vitro derived plantlets. A dozen RAPD (10-mer) and ten ISSR (dinucleotide contained repeats) primers were used for PCR and reproducible band profiles were obtained. The 84 and 81 distinct and scorable band classes (a total of 1,914 and 1,980 scorable bands) with an average of 7.0 and 8.1 bands per primer were obtained by RAPD and ISSR, respectively. Although higher numbers of bands were obtained by ISSR rather than RAPD, but none of the primers showed polymorphism among micropropagated plantlets and their respective mother plants. The profiles generated based on the two marker systems were found to be highly uniform and monomorphic. Cluster analysis further confirmed genetic stability of micropropagated plantlets. Jaccard’s similarity coefficients obtained for both markers in mother plants and their in vitro regenerants were estimated to be 1.00 but three sets of genotypes were grouped into two major clusters with similarity coefficients of 0.53 (RAPD) and 0.63 (ISSR). The molecular analyses precisely proved the production of genetically stable grape plantlets and certified the application of micropropagation protocol to be developed on a commercial scale.

Cotton cultivar Coker has been already transformed with recombinant pBI121-chi via Agrobacterium tumefaciens. The T-DNA region of pBI121-chi carries the chitinase (chi) gene from bean and is under the control of the CaMV35S promoter. T1 and T2 progenies of transgenic cotton containing the chi gene were used in this study. Polymerase chain reaction (PCR), Southern and Western blotting data confirmed integration and expression of the chi gene in the T1 and T2 progenies. The growth of Verticillium dahliae was singnificantly inhibited in an in vitro bioassay for which 100 μg of crude leaf protein extract derived from the T1 plants was used. The 850-bp expected chi fragment was amplified for 77 transgenic plants from 128 T1 and T2 progenies, and 75 transgenic plants showed both chi and nptII bands. T0 conduct bioassay, cotton seedlings were infected with the spore suspension (106 spores/ml), in a greenhouse. Fifty-five percent of the transgenic plants were able to restrict V. dahliae growth and symptoms. There were no distinguishable differences in the phenotypic appearance of transgenic plants compared to non-transgenics. These results showed that transgenic cotton expressing a bean chitinase exhibited enhanced resistance against V. dahliae in greenhouse and in-vitro assay as compared to the non-transgenic plants.:

The growth hormone gene could be an attractive candidate gene for milk production in goats. Single-strand conformation polymorphism was used to identify polymorphism at the goat growth hormone (gGH) gene. For this purpose, genotyping of 90 Talli goat breeds was performed. Nine conformational patterns were observed in exon 4 of the gGH gene, with frequencies of 27.7% for the homozygous pattern (AA) and 72.2% for all of other heterozygous patterns (A/B, A/C, A/B/C, A/B/D/E, A/B/C/F, A/C/F, A/B/E, A/B/F). The results showed that exon 4 of the GH gene in Talli goats is highly polymorphic: