title: [Preparation and identification of DNA G-quadruplex antibody].
abstract: OBJECTIVE
  To construct a prokaryotic expression plasmid of DNA G-quadruplex antibody, express it in E.coli BL21 (DE3) bacterial expression system, purify and identify the antibody.
  
  
  METHODS
  Chemically synthesized BG4 gene of DNA G-quadruplex antibodies was inserted into pSANG10 plasmid to construct DNA G-quadruplex antibody expression vector pSANG10-BG4. BL21 (DE3) as the host strain was utilized for self-induced expression of the protein. Osmotic lysis method was used for collecting this protein. Thereafter, the protein was purified by histidine tag affinity chromatography and identified by SDS-PAGE and Western blotting. The function of this protein was verified in SW480 colon cancer cells.
  
  
  RESULTS
  Double enzyme digestion and gene sequencing confirmed that DNA G-quadruplex antibody expression vector was successfully constructed. The relative molecular mass (Mr) of this protein was 30 000 to 37 000. The protein in a soluble form was expressed in the periplasm of BL21. The protein was of the same size as expected.
  
  
  CONCLUSIONS
  The DNA G-quadruplex antibody has been successfully prepared.
authors.affiliation: Department of Biochemistry and Molecular Biology, Shanxi Medical University, Taiyuan 030001; Department of Biochemistry, Changzhi Medical College, Changzhi 046000, China.
authors.forename: Yiqiang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Biochemistry and Molecular Biology, Shanxi Medical University, Taiyuan 030001, China.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Lan
authors.affiliation: Department of Biochemistry and Molecular Biology, Shanxi Medical University, Taiyuan 030001, China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Biochemistry and Molecular Biology, Shanxi Medical University, Taiyuan 030001, China.
authors.forename: Meining
authors.initials: M
authors.lastname: Li
authors.affiliation: Department of Biochemistry and Molecular Biology, Shanxi Medical University, Taiyuan 030001, China.
authors.forename: Zhirong
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Biochemistry and Molecular Biology, Shanxi Medical University, Taiyuan 030001, China.
authors.forename: Jinyan
authors.initials: J
authors.lastname: Shen
authors.affiliation: Department of Nephrology, Heji Hospital, Changzhi Medical College, Changzhi 046011, China.
authors.forename: Shuaishuai
authors.initials: S
authors.lastname: Shi
authors.affiliation: Department of Biochemistry and Molecular Biology, Shanxi Medical University, Taiyuan 030001, China.
authors.forename: Yuehong
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Biochemistry and Molecular Biology, Shanxi Medical University, Taiyuan 030001, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Xie
authors.affiliation: Department of Biochemistry and Molecular Biology, Shanxi Medical University, Taiyuan 030001, China.
authors.forename: Niuliang
authors.initials: N
authors.lastname: Cheng
mesh_terms: D000906:Antibodies / Q000235:genetics* / Q000276:immunology* / Q000302:isolation & purification / Q000378:metabolism; D045744:Cell Line, Tumor; D004247:DNA / Q000737:chemistry* / Q000276:immunology*; D004262:DNA Restriction Enzymes / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D054856:G-Quadruplexes; D005818:Genetic Engineering / Q000379:methods*; D005822:Genetic Vectors / Q000235:genetics; D006801:Humans; D010957:Plasmids / Q000235:genetics
chemical_list: D000906:Antibodies; D004247:DNA; D004262:DNA Restriction Enzymes