title: Refolding and structural characteristic of TRAIL/Apo2L inclusion bodies from different specific growth rates of recombinant Escherichia coli.
abstract: TNF-related apoptosis-inducing ligand (TRAIL/Apo2L) was produced mainly as inclusion bodies (IBs) by recombinant Escherichia coli with a temperature-inducible expression system. The yield of TRAIL type 2 IBs at higher preinduction specific growth rate (mu = 0.15 h-1) was higher than that of TRAIL type 1 IBs at lower preinduction specific growth rate (mu = 0.05 h-1). With the same optimized refolding protocols, two types of IBs exhibited different refolding features. Refolded type 1 IBs had higher recovery of more than 80% compared with type 2 IBs (57-63%). By the measurements of fluorescence and CD spectroscopy, type 1 TRAIL IBs dissolved by urea appeared to be a closer secondary structure to the native TRAIL than type 2. Furthermore, with trypsin treatment, the striking decrease in stability of type 1 IBs against protease digestion cannot be attributed to their small size particles observed by scanning electron microscope and probably depend on different protein structure properties between the two IBs. Different properties of inclusion bodies were mainly influenced by different physiological states of the cells just prior to the induction.
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, People's Republic of China.
authors.forename: Hui
authors.initials: H
authors.lastname: Kang
authors.forename: Ai-You
authors.initials: AY
authors.lastname: Sun
authors.forename: Ya-Ling
authors.initials: YL
authors.lastname: Shen
authors.forename: Dong-Zhi
authors.initials: DZ
authors.lastname: Wei
mesh_terms: D049109:Cell Proliferation; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D002479:Inclusion Bodies / Q000737:chemistry* / Q000648:ultrastructure*; D011487:Protein Conformation; D015202:Protein Engineering / Q000379:methods*; D017510:Protein Folding; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000737:chemistry* / Q000648:ultrastructure*
chemical_list: D011994:Recombinant Proteins; D053221:TNF-Related Apoptosis-Inducing Ligand; C505653:TNFSF10 protein, human