title: [Purification and stability studies of prokaryotic PDCD5 protein].
abstract: OBJECTIVE
  To set up an effective and simple purification method to obtain highly purified prokaryotic protein of PDCD5 and study its stability.
  
  
  METHODS
  Recombinant PDCD5 protein expressed in E. coli. was accumulated as an inclusion body. After washing, the inclusion body was denatured, renatured, digested with thrombine and then purified by two steps of chromatography. The purity of the products was analyzed by capillary electrophoresis and the stability was identified by SDS-PAGE.
  
  
  RESULTS
  Capillary electrophoresis showed that the purity of protein was 100%, and molecular weight was 15,800 with pI 5.9. Further bioactivity assay indicated that the purified PDCD5 could enhance the apoptosis of HL-60 cells withdrawing cytokine, which was in a dose-dependent manner. Stability analysis showed that the PDCD5 protein was sensitive to temperature and easy to degrade at 4 degrees C and 25 degrees C. However, it was relatively stable at -20 degrees C or lyophilized.
  
  
  CONCLUSIONS
  Highly purified and stable recombinant PDCD5 protein was obtained, which lays a foundation for the functional study and application investigation of PDCD5.
authors.affiliation: Peking University Center for Human Disease Genomics, Beijing 100083, China. wl159@263.net
authors.forename: Lu
authors.initials: L
authors.lastname: Wang
authors.forename: Hui
authors.initials: H
authors.lastname: Fan
authors.forename: Xiaoning
authors.initials: X
authors.lastname: Mo
authors.forename: Yingmei
authors.initials: Y
authors.lastname: Zhang
authors.forename: Zhengren
authors.initials: Z
authors.lastname: Wei
authors.forename: Yingcheng
authors.initials: Y
authors.lastname: Zhong
authors.forename: Dawu
authors.initials: D
authors.lastname: Huang
mesh_terms: D051017:Apoptosis Regulatory Proteins / Q000096:biosynthesis*; D004926:Escherichia coli; D006801:Humans; D002479:Inclusion Bodies; D009363:Neoplasm Proteins / Q000096:biosynthesis*; D011994:Recombinant Proteins / Q000096:biosynthesis*
chemical_list: D051017:Apoptosis Regulatory Proteins; D009363:Neoplasm Proteins; C117283:PDCD5 protein, human; D011994:Recombinant Proteins