Advanced Materials Research Vols. 641-642

Abstract: The analysis on codon usage bias of UL17 gene of duck enteritis virus (DEV) may provide a basis for understanding the relevant mechanism for its biased usage of synonymous codons and for selecting appropriate host expression systems to improve the expression of DEV UL17 gene. In this study the results indicate that codon usage bias of DEV UL17 gene strongly preferred to the synonymous with A and T at third codon position. The ENC values and GC3S contents of the codon usage bias of UL17 genes in DEV and the 20 reference herpesviruses were obviously different. In addition, we compared the codon usage bias of DEV UL17 gene with E.coli, yeast and human. There are 25 codons showing distinct usage differences between DEV and E. coli, 17 codons between DEV and yeast, 23 codons between DEV and human. Therefore, the yeast expression system is more suitable for heterologous expression of the DEV UL17 gene.

Abstract: Objective: The aim was to identify the codon usage bias between the newly identified Riemerella anatipestifer (RA) major facilitator superfamily mfs_1 gene (GenBank accession No.CP003388.1) and other reference bacteriums. Methods: A comparative analysis of the codon usage bias of the 18 bacteriums was performed by using the CodonW 1.4 program and CUSP (create a codon usage table) program of EMBOSS (The European Molecular Biology Open Software Suite). Results: The results showed obvious differences of the synonymous codon usage bias in the 18 bacteriums indicated by the Codon Adaptation Index (CAI), effective number of codons (ENc), and the value of G+C content at the 3rd codon position. The codon usage pattern of the major facilitator superfamily mfs_1 gene was phylogenetically conserved and similar to that of the major facilitator superfamily mfs_1 gene of the Elizabethkingia anophelis Ag1 Contig17, with a strong bias towards the codons with A and T at the 3rd codon position. A cluster analysis of codon usage pattern of the RA major facilitator superfamily mfs_1 gene with other reference bacteriums demonstrated that the codon usage bias of the major facilitator superfamily mfs_1 genes of the 18 bacteriums had a very close relation with their gene function. The ENc-plot revealed that the genetic heterogeneity in the RA major facilitator superfamily mfs_1 gene and the 18 reference bacteriums were constrained by G+C content, while gene length exerted relatively weaker influences. In addition, comparisons of the codon preferences in the major facilitator superfamily mfs_1 gene of RA with those of Escherichia coli, yeast and humans revealed that there were 36 codons showing distinct usage differences between the RA and E. coli, and 37 between the RA and humans, but only 28 between the RA and yeast. Therefore, the yeast system may be more suitable for the expression of the RA major facilitator superfamily mfs_1 gene. Conclusion: Together, these results may improve our understanding of the evolution, pathogenesis and functional studies of RA and possibly contribute significantly to the area of other bacteriums.

Abstract: The analysis on codon usage bias of OmpA/MotB gene of Riemerella anatipestifer (RA) may provide a basis for understanding the evolution and pathogenesis of RA and for selecting appropriate host expression systems to improve the expression of target genes in vivo and in vitro. In our study, a comparative analysis of the codon usage bias in the newly discovered RA OmpA/MotB gene and the OmpA/MotB gene of 20 reference flavobacteriaceae was performed. The results of the codon adaptation indes (CAI), effective number of codon (ENC), and GC3s values indicated that synonymous codon usage bias in the OmpA/MotB gene of flavobacteriaceae. The results showed that codon usage bias in the RA OmpA/MotB gene was strong bias towards the synonymous codons with A and T at the third codon position. A high level of diversity in codon usage bias existed, and the effective number of codons used in a gene plot revealed that the G+C compositional constraint is the main factor that determines the codon usage bias in OmpA/MotB gene of flavobacteriaceae. Comparison of the codon usage in the OmpA/MotB gene of different organisms revealed that there were 31 codons showing distinct codon usage differences between the RA and E. coli, 41 between the RA and humans, but 29 between the RA and yeast. Therefore the yeast expression system may be more suitable for the expression of RA OmpA/MotB gene. These results may improve our understanding of the evolution, pathogenesis and functional studies of RA, as well as contribute significantly to the area of flavobacteriaceae research.

Abstract: In this study, we calculated the codon usage bias in DPV CHv UL1 gene and performed a comparative analysis of synonymous codon patterns in UL1 of DPV CHv strain and other 19 reference herpesviruses. The results revealed that the synonymous codons with A and T at the third codon positon have widely usage in the codon of UL1 gene of DPV CHv. G + C compositional constraint was the main factor that determined the codon usage bias in UL1 gene. In addition, the codon usage bias of DPV CHv UL1 gene was compared with those of E. coli, yeast and human. There are 25 codons showing distinct usage differences between DPV and E. coli, 26 codons between DPV and yeast, and 21 codons between DPV and human. Therefore, the Human expression system is more suitable for heterologous expression of the DPV UL1 gene.

Abstract: In this paper, a corresponding analysis of the codon usage bias in the large subunit of ribonucleotide reductase (R1), encoded by UL39 gene from duck enteritis virus (DEV) CHv strain (Assigned Accession No.: EU071042) and 33 other reference herpesviruses was performed by using CAI, CHIPS and CUSP program of EMBOSS, aims to provide a basis for understanding the evolution and pathogenesis of DEV and for selecting appropriate host expression systems. The results showed that codon usage bias of DEV R1 gene strongly preferred to the synonymous with A and T at the third codon position; the phylogentic analysis revealed that DEV had a close evolutionary relationship with the avian Alphaherpesvirinae. In addition, the codon usage bias of DEV R1 gene was compared with those of E.coli, yeast and human. There are 17 codons showing distinct usage differences between DEV and E.coli, 13 codons between DEV and yeast, 20 codons between DEV and human. Therefore, the yeast expression system is more suitable for the target gene’s expression. The extent of codon usage bias in the DEV R1 gene was highly correlated with the gene expression level, therefore the results may provide useful information for the study of classification and function of the target gene.

Abstract: We measured the different performance of bio-diesel,which was used to compare with 0#diesel ,on the diesel engine YC6A220C without any adjustments. The result is that under the five different work condition,using bio-diesel has a good impact on protecting environment and reducing emission.Compared with 0#diesel,bio-diesel oil consumption rose by3.48%,but NOx and PM2.5 dramatically dropped by 15.20% and 3.67%.

Abstract: Direct Determination of L-Ter-Leucine in Enzyme Catalytic Reaction System by HPLC Was Studied. the Detection Were Performed on a Kromasil 700-5C18 Column Using a Eluant Containing 0.25% (NH4)H2PO4 and 100% Methanol (V((NH4)H2PO4):V(methanol)=100:5) with the Flow Rate of 0.8 Ml/min at,detection Wavelength of 205nm. there Was a Good Line Correlation between Peak Area and Contents in the Rang of 0.2-10 Mg/ml, the Correlation Coefficient Was 0.9986, the Average Recovery Was 98.88% with a Relative Stand Deviation of 0.78% (n=5). this Method Is Simple, Stable, Accurate and Reliable for the Quality Control of L–ter-Leucine.

Abstract: WD100, knocked out adhE of Escherichia coli SZ470 and inserted ldhA into Escherichia coli WD01, was genetically engineered to utilize xylose. D-lactate production was investigated for shake flask cultures with xylose. In 64h WD100 produce 10.1g/L D-lactate in the shaking flask And it consumed 25g/L xylose during the ending of fermentation.This volumetric productivity with xylose is 0.14 g·L^-1·h^-1.Because of pyruvate decarboxylase (poxB) expressed in flask fermention,acetate production was up to 4.7g/L.Succinate,formate,ethanol was also produced as a minor product during fermentation.

Abstract: Objective: To compare dose-volume histograms (DVHs) and the dose distribution of three-dimensional conformal radiotherapy(3DCRT),7 fields radiotherapy(7FRT) and intensity-modulated radiotherapy (IMRT) of treatment planning in gastric cancer. Methods: We selected 5 patients with gastric cancer, they were pathologically confirmed stage T3,T4 or N+ gastric cancer. All patients underwent radical gastrectomy. A dosimetry study was carried out on these five patients. For each patient, three kinds of treatment planning were designed with a prescribed dose of 45Gy to 95％of PTV.Many kinds of parameters of these plans in each patient were compared: isodose distributions line、dose-volume histogram(DVH)、V95%、V110%、CI、HI、EI of target volume and the dose of related critical organs. Results: IMRT was superior to 3DCRT and 7F-RT in dose uniformity（p＜0.05）, there was no statistical difference between 3DCRT and 7FRT in CI（p>0.05）.IMRT had better dose conformity than 3DCRT and 7FRT（p＜0.05）, and 3DCRT was better than 7FRT in CI（p＜0.05）.IMRT showed better EI than 3DCRT and 7FRT（p＜0.05）,there was no statistical difference between 3DCRT and 7FRT in EI（p>0.05）.IMRT had advantage at sparing liver compared with 3DCRT and 7FRT（p＜0.05）,7FRT showed better D1/3 of liver than 3DCRT（p＜0.05）,but there was no statistical difference between 3DCRT and 7FRT in Dmean of liver（p>0.05）.IMRT expressed better Dmax of spinal cord than 3DCRT and 7F-RT（p＜0.05）, and 7FRT was better than IMRT in Dmax of spinal cord（p＜0.05）.But the dose received by the both kidneys were not significantly different. Conclusion: IMRT is superior to 3DCRT and 7FRT,and 3DCRT plans showed better CI and Dmax of spinal cord composed to 7FRT,and 7FRT was superior to 3DCRT in D1/3 of liver. IMRT for gastric cancer had physics advantage for clinical application.

Abstract: Thymidylate synthase (TS) is an important target in cancer therapy, which is a folate-dependent enyme, catalyzing the de novo synthesis of dUMP. In this report, the effect of 5-flurorouracil (5-FU) on the regulation of TS gene expression was estimated in zebrafish. The results showed 5-FU could significantly increase the TS expression in zebrafish embryos. However, TS mRNA level were remained unchanged. To determine the effect of 5-FU and 5-FdUMP on translation of TS mRNA, a rabbit reticulocyte lysate translation system was used. Addition of 5-FU, not inhibited the translation of TS mRNA. While addition of 5-FdUMP, completely repressed the translation of TS mRNA. Therefore, induced expression of thymidylate synthase by 5-FU in zebrafish occurred in translational level, not in transcriptional level. The findings demonstrated that zebrafish TS protein was able to bind to its own cogate mRNA and the 5-FU regulated TS in the translational level. This is the first time to confirm that the regulation of TS is affected by TS and its cognant mRNA interaction in the whole animal level.