title: Expression and purification of recombinant bone morphogenetic protein-2 in E.coli.
abstract: OBJECTIVE
  To explore the method for producing human bone morphogenetic protein-2 (hBMP-2) by gene engineering techniques.
  
  
  METHODS
  E.coli BL21 was transformed with recombinant plasmid pYR (pBV220-hBMP-2) under different conditions, and SDS-PAGE analysis was conducted to observe the effects of the activation status and induction time of the bacterium on the target protein expression. The inclusion bodies obtained from E.coli were purified by anion exchange chromatography DEAE and molecular sieve S-300, and the recombinant protein was renatured by dialyse.
  
  
  RESULTS
  SDS-PAGE analysis showed a conspicuous band after induction signifying a new foreign protein with relative molecular mass of approximately 13 000. After activation of the bacteria when D600 was about 0.45, most efficient expression of rhBMP-2 was achieved which reached the peak 4 h after induction with heat. Implantation of the purified recombinant hBMP-2 resulted in proliferation of mesenchymal cells and new cartilage and bone formation, as shown by histological analysis 4 weeks after implantation.
  
  
  CONCLUSIONS
  hBMP-2 produced by gene engineering techniques possesses the biological capacity of ectopic bone formation.
authors.affiliation: Institute of Clinical Anatomy, First Military Medical University, Guangzhou 510515, China. ln-xsh@sohu.com
authors.forename: Shao-Hu
authors.initials: SH
authors.lastname: Xiong
authors.forename: Lei
authors.initials: L
authors.lastname: Yu
authors.forename: Hai-Yan
authors.initials: HY
authors.lastname: Tan
authors.forename: Tao
authors.initials: T
authors.lastname: Huang
authors.forename: Chao-Yang
authors.initials: CY
authors.lastname: Wang
authors.forename: Da-Yong
authors.initials: DY
authors.lastname: Liu
authors.forename: Shi-Zhen
authors.initials: SZ
authors.lastname: Zhong
mesh_terms: D000818:Animals; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics*; D005260:Female; D006801:Humans; D008297:Male; D051379:Mice; D010012:Osteogenesis / Q000187:drug effects; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000378:metabolism; D016212:Transforming Growth Factor beta
chemical_list: C525718:BMP2 protein, human; C525719:Bmp2 protein, mouse; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2