The fused gene (PTH-HSA) of parathyroid hormone (PTH) gene and Human Serum Albumin(HSA) gene was amplified without linker by Overlapping PCR technology. The spliced gene was clone into Pichia pastoris secretory vector pPIC9K. With the help of promoter AOX1 and mat ? signal peptide, the PTH-HSA gene was designed to secretory expression.Linearized by restriction enzyme SalI, The recombinant plasmid pPIC9K/PTH-HSA was transformed into Pichia pastoris KM71 by electroporation. The recombinant strains which were identified by G418 and PCR analysis were induced by methanol to express protein PTH-HSA. The target protein was expressed in fermentation supernatant. Western blot analysis of the fusion protein showed that the expressed fusion protein PTH-HSA had the antigenicity of HSA.adenylate cyclase assay proved that the fused protein exhibited the bioactivity to stimulate cAMP synthesis The specific activity of broth was about 318IU/ml.

The hom gene encoding for homoserine dehydrogenase was amplified from the genomic DNA of Corynebacterium glutamicum ATCC 13032.After the kanamycin-resistant gene(Km)cassette from plasmid pET28a was inserted into the center of hom,the hom::Km cassette was then electroporated into the competent cell of C.glutamicum ATCC 13032.And kanamycin-resistant clones were obtained.PCR was performed to confirm whether the Km gene was integrated into the hom gene of these clones and the recombinant strains of hom-disrupted were screened out.Fermentation results showed that the lysine yield of the hom-disrupted strain C.g-hom::Km-8 reached 4.7 g/L,which was 6.7 times that of C.glutamicum ATCC 13032.

In order to isolate genes related with the osmoadaptation and glycerol metabolism of Candida glycerinogenes, a transformation system based on the dominant selectable marker Zeocin and restriction enzyme-mediated integration (REMI) was established. Effects of seven restriction enzymes on transformation efficiency of C.glycerinogenes were tested. Transformation conditions were optimized in the presence of Hind III. Under the optimal conditions of OD_ 600 ≈1.3, voltage of 1.5 kV, 2.0?10~9 competent cells/mL, 100 units of Hind III added, the transformation efficiency was up to 129 trnaformants/?g DNA. 58% of transformants were stable on nonselective medium. These results suggest that REMI technique would be beneficial to the genetic transformation of C.glycerinogenes.

A method to determine dihydroxyacetone (DHA) in fermentation broth was developed by high performance liquid chromatography (HPLC). DHA was separated on a Alltima C18(5?m,250?4.6mm). The mobile phase was 0.5% methanol solution (pH adjusted to 3.0 with H3PO4), the flow-rate was 1.0 ml/min and the detective wavelength was 200 nm. The detection limits of DHA was 0.1 g/L～10.0 g/L. 6.2 g/L DHA in the fermentation broth was detected by HPLC, which was in agreement with the result by spectrophotometric method.The method was applicable for DHA determination in the fermentation process.

More than 20 strains capable of producing dihydroxyacetone from glycerol were isolated from 4 different natural environment samples by using two detection methods. The strain 6-8 which could grow on medium containing glycerol as sole carbon source had a higher converting capability. Under a better culture, the highest DHA production of the strain 6?8 reached 6.4 g/L. In addition to general morphological and bio-chemical characteristics, the strain 6?8 was identified by 16S rDNA sequence and systematic analysis. The results showed that 16S rDNA sequence of the strain 6-8 had similarity of 99.7% with Acinetobacter sp. suggesting that the strain 6-8 is one of subspecies of Acinetobacter sp.

Nicotiana tabacum is an important and classical model plant which can respond to the change of environmental conditions by accumulating osmoprotectants, such as glycerol and proline which contribute to the re-establishment of homeostasis when exposed to various adverse environmental stresses, such as drought, salinity, high and low temperatures. The optimization of ultrasonic extraction (UE) conditions of glycerol-3-phosphate dehydrogenase (GPDH) of tobacco leaf have been built by orthogonal test. It showed that optimum of the powers, treatment times, slot times and leaf-to-solvent ratios of UE was 75w, 2h, 2s, and 1[DK]∶12 g/ml, respectively. Under these conditions, the activity of GPDH has been tested as 0.3937U/mg protein, which was higher than other extraction methods such as liquid nitrogen and grinding on ice bath. According to investigation, it is the first description of determination of content of GPDH with ultrasonic in tobacco. It could provide basis for the further research in the relation of content of glycerol and osmotic pressure in tobacco.

The method for analysis and determination the cleavage of soybean sterol, in which the soybean sterol was degraded and the products androst-1,4-diene-,17-dione (ADD) and androst-4-ene-3,17-dion (AD) were developed by Liquid Chromatography-mass Spectrometry. The HPLC conditions adopted were: a All- tima ODS-2 column (250 mm?4.6 mm, 5 ?m), a mobile phase consisted of menthanol-water (70:30), a flow rate of 1.0 mL/min, a room column temperature. and the detective wavelength was 244 nm.The ZMD Micromass electrospray ionization (ESI)-mass spectrometer was employed. In such conditions the corre- sponding HPLC chromatogram and MS spectrum were obtained. The method has a linear ranger of 0.01 mg/mL ~ 0.09 mg/mL, R2 =0.9999, the recoveries of ADD and AD were 102.6% and 105.90%, the RSD of ADD and AD were 3.02%, 3.5% and 3.08%, 3.24%. This method showed high sensitivity, accuracyand easy to perform. It is suitable to analysis the process cleavage of soybean sterol as well as quality control of product.

Effect of organic acids on the synthesis of 1,3 propanediol was studied.The adsorption of organic acids from glycerol fermentation liquor by ion-exchange resins was investigated.The results showed that organic acid and 1,3 propanediol production was in negative relationship.The static adsorption showed that ion-exchange resin 005 had the best adsorption abilities of the organic acids in the glycerol fermentation liquor.It was showed that the yield of 1,3propanediol increased by 166% after the extraction of organic acids from glycerol fermentation liquor and the convertion rate increased by 34%.

Objective To investigate the binding ability of the terminase large subunit of Pseudomonas aeruginosa bacteriophage PaP3 to the cos site. Methods The gene tls was amplified from the genome of bacteriophage PaP3 by PCR and subcloned into pMD18-T vector. Then the gene tls cut down from the vector was inserted into the plasmid pQE31 which could give a 6-His tag at the N-terminal of the expressed protein. The recombinant vector pQE-tls was transformed to E.coli. JM109, after induction with IPTG, the expressed bacteria were resuspended and sonicated, then after centrifugation, the inclusion body was obtained. The inclusion body was dissolved with lysis buffer, then the tagged protein was purified by Ni-NTA affinity chromatography and renatured by dialysis. Finally the DNA-binding ability of the fusion protein rTLS was determined by EMSA. Results The expression plasmid pQE31-tls was successfully constructed, and the target protein yield was up to 30% of the total bacterial proteins. After purification and renaturation, the fusion protein rTLS can partially bind the cos fragment. Conclusion The fusion protein rTLS was successfully expressed, purified and renatured. The rTLS has the specific DNA-binding activity. The present work lays the foundation for the further research of the gene tls.

AIMTo investigate the quality and optimized test methods and establish the quality specification of recombinant adenovirus-IL2.

METHODSThe titer of Adv-IL2 was measured by cytopathic effect (CPE). Hela cells were infected with Adv-IL2 in vitro, the expressed IL-2 and its bioactivity in Hela cell were determined by enzyme-linked immunosorbent assay (ELISA) and 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide (MTT) respectively. The purity of Adv-IL2 was analysed by UV and IE-HPLC method. The molecular weight and enzyme digestive map of Adv-IL2 genome were analysed by electrophoresis. The characteristic gene E2B, IL-2 expression casseter and foreign factors (RCV, HIV, HBV, HCV) were detected with polymerase chain reaction (PCR). Other tests were carried out according to the Chinese Requirements for Biological Products.

RESULTSAdv-IL2 was generated efficiently with a titer of 3 x 10(10) pfu.mL-1. The expressed IL-2 and its bioactivity were 25 ng.mL-1 and 700 u.mL-1 respectively. A260 nm/A280 nm was 1.23. The purity determined by IE-HPLC was higher than 98%. The molecular weight, enzyme digestive map of Adv-IL2 genome, the characteristic gene E2B and IL-2 expression casseter conformed to expected values.

CONCLUSIONThe specification for Adv-IL2 is established and can be used for the quality control of the product.

Adenoviridae ; genetics ; Cell Line ; Embryo, Mammalian ; Genetic Vectors ; genetics ; HeLa Cells ; virology ; Humans ; Interleukin-2 ; biosynthesis ; genetics ; Quality Control ; Recombinant Proteins ; biosynthesis ; Transfection