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Publications (5)0 Total impact

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    ABSTRACT: The synthetic biology matures to promote the heterologous biosynthesis of the well-known drug paclitaxel that is one of the most important and active chemotherapeutic agents for the first-line clinical treatment of cancer. This review focuses on the construction and regulation of the biosynthetic pathway of paclitaxel intermediates in both Escherichia coli and Saccharomyces cerevisiae. In particular, the review also features the early efforts to design and overproduce taxadiene and the bottleneck of scale fermentation for producing the intermediates.
    Yao xue xue bao = Acta pharmaceutica Sinica 02/2013; 48(2):187-92.
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    ABSTRACT: NADPH-cytochrome P450 reductase (CPR), a partner for P450 monooxygenases, serves as the electron donor to almost all eukaryotic cytochrome P450s. One cDNA (TchCPR) encoding cytochrome P450 reductase of T. chinensis was isolated from callus cells. The cDNA contains an open reading frame of 2154 nucleotides which encodes a protein of 717 amino acid residues. The TchCPR has higher similarity to other CPRs of gumnosperms (>82%) than that of angiosperms (<74%). The recombinant full-length TchCPR and a series of N-terminal truncated constructs with N-terminal fusion of His Tag were obtained and induced to express in E. coli B121(DE3), and then purified using affinity chromatography. The truncated forms of N-terminal more than 61 amino acid residues could be efficiently expressed while the truncated mutant of N-terminal 48 amino acid residues and the wild-type TchCPR were not successfully expressed in E. coli cells. The activity of the truncated TchCPR was assayed by measuring the reduction of cytochrome C. The electron transfer activity of the recombinantly purified CPRT61 was 1.6057 nmol of cytochrome C reduced per min per microg TchCPR reductase, and it is higher than that of the other four truncated forms.
    Hereditas (Beijing) 11/2010; 32(11):1187-94.
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    ABSTRACT: Influenza A/H1N1 virus-encoded nonstructural, or NS1, protein inhibits the 3'-end processing of cellular pre-mRNAs by binding the cellular protein: the 30-kDa subunit of CPSF (cleavage and polyadenylation specificity factor, CPSF30). CPSF30 binding site of the NS1 protein is a potential target for the development of drugs against influenza A/H1N1 virus. A yeast two-hybrid screening system was constructed and used for screening Chinese medicines that inhibit the interaction of the A/H1N1 flu NS1 protein and human CPSF30 protein. The NS1 gene of A/H1N1 virus was amplified by consecutive polymerase chain reaction (PCR), and the human CPSF30 gene of HeLa cell cloned by reverse transcriptase-polymerase chain reaction (RT-PCR). Then the two gene fragments confirmed by sequencing were subcloned into the yeast expression vectors pGBKT7 and pGADT7, respectively. The two constructs, bait vector pGBKNS1 and prey vector pGADCPSF, were co-transformed into yeast AH109. The eight individual yeast colonies were picked and subjected to verification by PCR/gel electrophoresis. The inhibition of the NS1-CPSF30 interaction was allowed the identification of selective inhibitors. The four of more than thirty identified Chinese medicines, including 'Shuanghuanglian oral liquid', showed the strong inhibition of the NS1-CPSF30 interaction.
    Yao xue xue bao = Acta pharmaceutica Sinica 03/2010; 45(3):388-94.
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    ABSTRACT: The gene encoding amorpha-4, 11-diene synthase was cloned from Artemisia annua L. Other two genes encoding the FPP synthase (FPPS) and HMG-CoA reductase (HMGR) were cloned from Saccharomyces cerevisiae. The cloned cDNAs were confirmed by DNA sequencing. Two expression vectors were constructed, one is named pGBT9/A/HMG/FPP harboring genes for HMG-CoA reductase and FPP synthase and the other is pYeDP60/G/AS, containing the gene encoding amorpha-4,11-diene synthase. Two kinds of engineered yeast were constructed: the first was named WHT [AS], which contained the plasmid pYeDP60/G/AS; the second was WHT [HMG + FPP + AS], in which the vectors pGBT9/A/ HMG/FPP and pYeDP60/G/AS were introduced by cotransformation mediated with LiOAc and PEG4000. The positive clones were identified for further fermentations. The samples from fermentations were analyzed by GC-MS for amorpha-4,11-diene. The results show that engineered yeasts could produce amorpha-4,11-diene. Moreover, the amorpha-4,11-diene production of WHT[ HMG + FPP + AS] and WHT[ AS] were 23.6 mg x L(-1) and 10 microg x L(-1), respectively. Its concentrations were reported as equivalents of valencene. The results showed the copy number increase of HMGR and FPPS genes can improve the production of amorpha-4, 11-diene in the fermentation of engineered yeasts.
    Yao xue xue bao = Acta pharmaceutica Sinica 01/2008; 42(12):1314-9.
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    ABSTRACT: Cloning and bioinformatics analysis of P450 cDNA in Artemisia annua. A P450 cDNA gene was cloned from A. annua by RT-PCR. The bioinformatics analysis of the P450 gene was performed. The complete ORF of this P450 cDNA is 1 464 bp and encodes 488 aa. The sequence was reported to GenBank and coded as DQ667171. Bioinformatics analysis of the P450 cDNA showed it encoded an A-type P450 protein with 54. 992 kDa, it's isoelectric point was 8.83 and the possibility of export to mitochondria was 0.893 2. The comparable analysis of the P450 with CYP71AV1 revealed that the two proteins probably performed the same function because of the similar character.
    Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica 12/2007; 32(21):2227-31.