1.Expression of a protein elicitor pebC1 from Botrytis cinerea in Pichia pastoris.
Yunhua ZHANG ; Xiufen YANG ; Yanfeng LIU ; Shanjiang YU ; Dewen QIU
Chinese Journal of Biotechnology 2011;27(11):1631-1636
In order to express PebC1 in Pichia pastoris, the pebC1 sequence was amplified from genome Botrytis cinerea BC-4-2-2-1 by PCR and subcloned into the Pichua pastoris expression vector pPIC9K to generate pPIC9K-pebC1. The recombinant plasmid was linearized by Bgl II and transformed into Pichia pastoris GS115 by electroporation. Recombinant Pichia pastoris GS115/pPIC9K-pebC1 was screened by MD and G418-YPD plates and further confirmed by PCR. The protein expression was induced by methanol and analyzed by SDS-PAGE. SDS-PAGE analysis showed a special band about 39 kDa and western blotting indicated a good antigenicity of the expressed protein. Bioassay results showed that the recombinant protein PebC1 can induce resistance to gray mould disease of cucumber and Arabidopsi thaliana.
Botrytis
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chemistry
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Fungal Proteins
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biosynthesis
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genetics
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pharmacology
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Pichia
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genetics
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metabolism
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Plant Diseases
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prevention & control
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Recombinant Proteins
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biosynthesis
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genetics
;
pharmacology
2.Synthesis of recombinant blood coagulation factor VIII (FVIII) heavy and light chains and reconstitution of active form of FVIII.
Sang Hwan OH ; Mi Young LEE ; Dong Weon SONG
Experimental & Molecular Medicine 1999;31(2):95-100
FVIII is synthesized as a single chain precursor of approximately 280 kD with the domain structure of A1-A2-B-A3-C1-C2 and it circulates as a series of metal ion-linked heterodimers that result from cleavages at B-A3 junction as well as additional cleavages within B domain. Factor VIII is converted to its active form, factor VIIIa, upon proteolytic cleavages by thrombin and is a heterotrimer composed of the A1, A2, and A3-C1-C2 subunits. A1 subunits of factor VIIIa terminates with 36 residue segment (Met337-Arg372) rich in acidic residues. This segment is removed after cleavages at Arg336 by activated protein C, which results in inactivation of the cofactor. In the present study, site-directed mutagenesis of FVIII at Arg336 to Gln336 was performed in order to produce an inactivation resistant mutant rFVIII (rFVIIIm) with an extended physiological stability. A recombinant mutant heavy chain of FVIII (rFVIII-Hm; Arg336 to Gln336) and wild-type light chain of FVIII (rFVIII-L) were expressed in Baculovirus-insect cell (Sf9) system, and a biologically active recombinant mutant FVIII (rFVIIIm) was reconstituted from rFVIII-Hm and rFVIII-L in the FVIII-depleted human plasma containing 40 mM CaCl2. The rFVIIIm exhibited cofactor activity of FVIIIa (2.85 x 10(-2) units/mg protein) that sustained the high level activity during in vitro incubation at 37 degrees C for 24 h, while the cofactor activity of normal plasma was declined steadily for the period. These results indicate that rFVIIIm (Arg336 to Gln336) expressed in Baculovirus-insect cell system is inactivation resistant in the plasma coagulation milieu and may be useful for the treatment of hemophilia A.
Animal
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Baculoviridae/genetics
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Blotting, Western
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Cell Line
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Factor VIII/metabolism*
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Factor VIII/genetics
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Factor VIII/chemistry
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Factor VIII/biosynthesis
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Genetic Vectors
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Human
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Mutagenesis, Site-Directed
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Recombinant Proteins/metabolism
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Recombinant Proteins/genetics
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Recombinant Proteins/chemistry
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Recombinant Proteins/biosynthesis
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Spodoptera
3.Study on the reconstitution in vitro and photochemical activities of phytochrome from the Synechocystis sp. PCC6803.
Yi-Ran DONG ; Yong RAN ; Kai-Hong ZHAO ; Ming ZHOU
Chinese Journal of Biotechnology 2004;20(2):238-244
Genomic DNA sequence analysis of phytochrome like photoreceptors in a number of bacteria revealed several open reading frames (ORFs) encoding proteins with amino acid sequences homologous to plant phytochromes. The phytochrome like photoreceptors, collectively called bacteriophytochromes, contain an N-terminal domain homologous to the chromophore-binding domain (CBD) of higher plants and a C-terminal domain of histidine kinase domain( HKD). Due to their simple structure, bacteriophytochromes broaden the view of phytochrome evolution and provide us with a simple model to investigate phytochrome-mediated light signal in higher plants. In this report, the bacteriophytochromes from Synechocystis sp. PCC6803 were investigated. The gene cph1 and its fragment cph1 (C-435) were isolated from the Synechocystis sp. PCC6803 genomic DNA by polymerase chain reaction(PCR) using specific primers. Then, the genes were cloned with the vector pBluescript, yielding plasmids pBlu-cphl and pBlu-cph1 ( C-435), before they are subcloned with the vector pET30, using the EcoRV and Xho I restriction sites. pBlu-cph1, pBlu-cph1 (N-435) were cleaved with Sma I and Xho I, and the released genes were ligated to the pET30a fragment. The E. coli [strain BL21 (DE3)] cells containing recombinant pET30a were grown in medium RB at 20 degrees C, and harvested 6 h later after induction with isopropyl thio-beta-D-galactoside (IPTG). Then, reconstitution systems were employed to study the characteristics of the genes. In the reconstitution system, autoassembly of aprotein of phytochrome with PCB was investigated. The chromophore addition was an autocatalytic process. Reconstitution products were red/infrared (R/FR) photochromic, which was similar to that of the phytoehrome in higher plants. How ever, the spectral change ratios (deltaAmax/deltaAmin) of the two fragments differed from each other. It was also shown that PCB was covalently bound to apo-protein via Zn2+ fluoresc ence SDS-PAGE. After irradiation by light of 700 nm, the maximum absorption spectrum o f holo-Cphl was 650nm. The absorption of it after denaturatior in the dark with ur ea in the presence of hydrochloric acid (pH = 2) was 660nm, which was similar with th at of cis-PCB. In addition, after irradiation by light of 650nm, the maximum absorption spectrum of holo-Cph1 was 700nm. The absorption of it after denaturation in the dark with urea in the presence of hydrochloric acid (pH = 2) was 600nm, which was similar with that of trans-PCB. The result showed that the photochromism of phytochrome resulted from the isomerizaation of chromophore (PCB in this report). The reconstitution of Cph1 (C-435) under the same condition supported the conclusion. Fluorescence emission spectrum of the products suggested that bacteriophytochrom e structure with cis-PCB was more stable than that with trans-PCB. The new reconstitution system in this report sets a base for the application of phytochrome as photochromic biomaterials in biosensors. In addition, phytochrome shows great potential in food, cosmetic and biological engineering, etc.
Bacterial Proteins
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biosynthesis
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chemistry
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genetics
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Cloning, Molecular
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Escherichia coli
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genetics
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metabolism
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Gene Expression Regulation, Bacterial
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radiation effects
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Genetic Vectors
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Photochemistry
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Phytochrome
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biosynthesis
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chemistry
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genetics
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Protein Kinases
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biosynthesis
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chemistry
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genetics
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Recombinant Proteins
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biosynthesis
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chemistry
;
genetics
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Synechocystis
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chemistry
4.High-level production of alkaline polygalacturonate lyase in recombinant Pichia pastoris.
Yun WANG ; Zhaozhe HUA ; Liming LIU ; Zhaohui ZHANG ; Guocheng DU ; Jian CHEN
Chinese Journal of Biotechnology 2008;24(4):635-639
In order to increase the production of alkaline polygalacturonate lyase (PGL) by recombinant Pichia pastoris GS115, the effect of cell and methanol concentration on the PGL production was carefully investigated by single factor experiment. The optimum conditions were listed as follows: the cell concentration 122 g/L, the methanol concentration 20 g/L, and the ratio of methanol and cell concentration 0.16-0.20 g/g (methanol/cell). With the glycerol and methanol feeding strategies, the ratio of methanol and cell concentration could be controlled at the range of 0.171 to 0.195 g/g. And the highest PGL activity (430 u/mL) and highest PGL productivity (4.34 u/mL/h) were achieved.
Alkalies
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metabolism
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Fermentation
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Genetic Vectors
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Methanol
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chemistry
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Pichia
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enzymology
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genetics
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Polysaccharide-Lyases
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biosynthesis
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genetics
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Recombinant Proteins
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biosynthesis
;
genetics
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Recombination, Genetic
5.Optimization of fermentation of recombinant human Endostatin (rh-Endostatin) expression in Escherichia coli.
Guo-Dong CHANG ; Zhuang-Lin LI ; Jia-Yang QIN ; Cui-Qing MA ; Yong-Zhang LUO ; Ping XU
Chinese Journal of Biotechnology 2005;21(4):662-666
The fermentation process of recombinant human Endostatin expression in Escherichia coli BL21 (DE3) was studied. The effects of factors such as concentration of IPTG, induction time, cultivation temperature and feeding strategies were investigated. Beside that, by changing the temperature to 40 degrees C after induction, the high-density cultivation finished in a much shorter period. After 9 hours cultivation, the optical density (OD) at 600 nm reached 140 and the yield of inclusion body was 3 g/L. While E. coli system was used, protein with better activity and stability was obtained. The cost was much lower and the producing process was much steadier. It will meet the demands of the industrial production.
Endostatins
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biosynthesis
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genetics
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Escherichia coli
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genetics
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growth & development
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metabolism
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Fermentation
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Humans
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Protein Engineering
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Recombinant Proteins
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biosynthesis
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genetics
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Thiogalactosides
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chemistry
6.Synthesis of glucose laurate monoester catalyzed by Candida antarctica lipase B-displaying Pichia pastoris whole-cells.
Suiping ZHENG ; Changqiong REN ; Shuangyan HAN ; Ying LIN
Chinese Journal of Biotechnology 2009;25(12):1933-1939
We developed a new enzymatic-catalyzing producing process of glucose laurate monoester. In the process we used Candida antarctica lipase B-displaying Pichia pastoris whole-cells as biocatalyst, glucose as the acyl acceptor and lauric acid as the acyl donor. The product glucose laurate monoester was purified by silica gel column chromatography and preparative liquid chromatography, and identified by liquid chromatography-mass spectrometry. Then we optimized the process from various aspects, such as solvent composition, ratio of dmethyl sulfoxide to 2-Methyl-2-butanol (V/V), catalyst dosage, substrate concentration, water activity and temperature. The optimal reaction conditions were: glucose 0.5 mmol/L, lauric acid 1.0 mmol/L, ratio of 2-Methyl-2-butanol to Dmethyl sulfoxide is 7:3 in 5 mL volume, temperature 60 degrees C, the best initial water activity of whole-cells biocatalyst is 0.11. The maximum glucose conversion could be 48.7% after 72 h.
Biocatalysis
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Candida
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enzymology
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Esters
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chemistry
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metabolism
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Fungal Proteins
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Genetic Engineering
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Glucose
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chemistry
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metabolism
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Laurates
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chemistry
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metabolism
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Lipase
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biosynthesis
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genetics
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Pichia
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genetics
;
metabolism
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Recombinant Proteins
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biosynthesis
;
genetics
7.X-ray diffraction analysis of glycoprotein D from herpes simplex virus type 2.
Zhujun CHEN ; Guangwen LU ; Jianxun QI ; Xiang XU ; Na ZHANG ; Jinghua YAN ; Rongfu WANG
Chinese Journal of Biotechnology 2011;27(10):1499-1506
Glycoprotein D (gD) of Herpes simplex virus type 2 (HSV-2) is a key factor mediating the entry of HSV-2 into host cells. In order to explain the mechanism underlying the gD-mediated receptor-binding and viral entry, we performed a structural study on HSV-2 gD. The ectodomain of the gD protein encompassing residues 1 to 285 was expressed by baculovirus-infected insect cells as a secreted soluble protein with a C-terminal hexa-his tag. The protein was then purified by affinity and size-exclusion chromatography. The purified protein was successfully crystallized using the hanging-drop vapor-diffusion at 18 degrees C in a condition consisting of 0.1 mol/L Hepes pH 7.2, 5% (V/V) 2-methyl-2,4-pentanediol (MPD) and 10% PEG 10 000. The crystals diffracted to 1.8 angstroms resolution and belonged to space group P21, with unit-cell parameters alpha = 63.6, b = 55.4, c = 65.3 angstroms, beta = 96.3 degrees.
Animals
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Baculoviridae
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Crystallization
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Crystallography, X-Ray
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Herpesvirus 2, Human
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chemistry
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Insecta
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genetics
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metabolism
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Recombinant Proteins
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biosynthesis
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chemistry
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genetics
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Viral Fusion Proteins
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biosynthesis
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chemistry
;
genetics
8.Construction of protease resistant mutein of human CNTF and its expression in Pichia pastoris.
Hong-Liang ZHAO ; Chong XUE ; Xiang-Hua XIONG ; Wei ZHANG ; Hou-Chu ZHU ; Zhi-Min LIU
Chinese Journal of Biotechnology 2004;20(3):394-397
AX15 is a mutein of naturally occurring human ciliary neurophic factor (hCNTF), with improved biological activity, stability and solubility. AX15 is susceptible to protease degradation when expressed in Pichia pastoris. Amino acid sequencing revealed the degradation was occurred behind position 12 and 13 amino acid residues, which constitute a dibasic site, RR. Based on the substrate specificity of KEX2, a KEX2 resistant mutein of AX15-AX15 (R13K) was constructed, in which RR was replaced by RK. It was demonstrated that the stability of AX15 (R13K) improved significantly, as no degradation was detected even after 120 hours of induction. AX15 (R13K) was purified to homogeneity by ultrafiltration and gel filtration. TF-1 cell survival bioassay showed AX15 (R13K) had equivalent specific activity to AX15. The protease resistant mutein of AX15 may have greater in vivo stability and thus have superior therapeutic potential.
Ciliary Neurotrophic Factor
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biosynthesis
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genetics
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Genetic Vectors
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Humans
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Mutant Proteins
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biosynthesis
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genetics
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Mutation
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Peptide Hydrolases
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chemistry
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Pichia
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genetics
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metabolism
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Recombinant Proteins
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biosynthesis
;
genetics
;
isolation & purification
9.Overexpression of response gene to complement-32 promotes cytoskeleton reorganization in SW480 cell line.
Jie TIAN ; Chuan XU ; Min-hui YANG ; Zu-guo LI
Journal of Southern Medical University 2011;31(7):1179-1182
OBJECTIVETo construct the recombinant plasmid pcDNA3.0-RGC32 and evaluate the effect of the response gene to complement-32 (RGC32) on cell cytoskeleton in vitro.
METHODSThe full-length cDNA of RGC32 was obtained by RT-PCR and inserted into the eukaryotic expression vector pcDNA3.0 to generate the recombinant plasmid pcDNA3.0-RGC32. After transfection of the recombinant plasmid into SW480 cells, the expression of RGC32 in the cells was detected by Western blotting. The cytoskeleton of SW480 cells was visualized before and after the transfection, and the changes in the cell migration ability was assessed by wound-healing assay.
RESULTSThe recombinant plasmid pcDNA3.0-RGC32 was successfully constructed. The expression of RGC32 was significantly increased in SW480 cells after transfection with pcDNA3.0-RGC32. Before the transfection, the microfilaments of SW480 cells were few and short without obvious polarity, but after the transfection, the microfilaments were increased and elongated with also an obvious polarity, and the invasive structures of lamellae and lamellipodia occurred. The migration ability of the cells was enhanced after transfection with pcDNA3.0-RGC32.
CONCLUSIONOverexpression of RGC32 can cause the reorganization of cytoskeleton and promotes the cell migration, which can be an important mechanism of RGC32 in promoting cancer metastasis.
Cell Cycle Proteins ; biosynthesis ; genetics ; Cell Line, Tumor ; Cell Movement ; Colorectal Neoplasms ; genetics ; metabolism ; pathology ; Cytoskeleton ; chemistry ; metabolism ; Genetic Vectors ; Humans ; Muscle Proteins ; biosynthesis ; genetics ; Neoplasm Metastasis ; genetics ; Nerve Tissue Proteins ; biosynthesis ; genetics ; Plasmids ; genetics ; Recombinant Proteins ; biosynthesis ; genetics
10.Fusion expression and bioactivity comparison of porcine beta-defensin-2 and porcine interferon-gamma in Pichia pastoris.
Dingyong ZHANG ; Lei SUN ; Limin YANG ; Wenjun LIU
Chinese Journal of Biotechnology 2010;26(12):1652-1659
In order to study PBD-2 and PoIFNgamma, the chimeric gene PBD-2-PoIFNgamma was synthesized by overlap extension PCR, and amplified PoIFNgamma on the basis of this sequence, then cloned into yeast expression vector pPICZalphaA separately to get the recombinant plasmid pPICZalphaA-PBD-2-PoINFgamma and pPICZalphaA-PoINFgamma. The recombinant plasmid was digested by Sac I and introduced into Pichia pastoris X33 cells by electroporation. Positive clones were screened and cultivated in BMMY medium containing 0.5% methanol for 72 h. SDS-PAGE and Western blotting analysis showed that the screened recombinant could secrete PBD-2-PoINFgamma and PoINFgamma separately. The activity of fusion protein was not detected by cytopathic effect inhibition assay and agar diffusion assay, but detected obvious antiviral activity of PoINFgamma. The helix and random coil contents was showed vary greatly between PoIFNgamma and PBD-2-PoLNFgamma by circular dichroism analysis. It was speculated that the fusion protein was not correctly folded and may affect the activity of PBD-2-PoINFgamma.
Animals
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Genetic Vectors
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genetics
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Interferon-gamma
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biosynthesis
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genetics
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Pichia
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genetics
;
metabolism
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Recombinant Fusion Proteins
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biosynthesis
;
chemistry
;
genetics
;
Swine
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beta-Defensins
;
biosynthesis
;
genetics