title: Co-expression of Dsb proteins enables soluble expression of a single-chain variable fragment (scFv) against human type 1 insulin-like growth factor receptor (IGF-1R) in E. coli.
abstract: Type 1 insulin-like growth factor receptor (IGF-1R) is a promising therapeutic target for cancer treatment. A single-chain variable fragment (scFv) against human IGF-1R forms inclusion body when expressed in periplasmic space of E. coli routinely. Here, we described that co-expression of appropriate disulfide bonds (Dsb) proteins known to catalyze the formation and isomerization of Dsb can markedly recover the soluble expression of target scFv in E. coli. A 50 % recovery in solubility of the scFv was observed upon co-expression of DsbC alone, and a maximum solubility (80 %) was obtained when DsbA and DsbC were co-expressed in combination. Furthermore, the soluble scFv present full antigen-binding activity with IGF-1R, suggesting its correct folding. This study also suggested that the selection of Dsb proteins should be tested case-by-case if the approach of co-expression of Dsb system is adopted to address the problem of insoluble expression of proteins carrying Dsb.
authors.affiliation: Department of Medical Technology, Medical College, Hebei University of Engineering, 199 South GuangMing Road, Handan, 056038, China, xw_sunny@163.com.
authors.forename: Xue-Wen
authors.initials: XW
authors.lastname: Sun
authors.forename: Xiao-Hua
authors.initials: XH
authors.lastname: Wang
authors.forename: Yan-Bing
authors.initials: YB
authors.lastname: Yao
mesh_terms: D001709:Biotechnology / Q000379:methods*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000378:metabolism*; D006801:Humans; D011485:Protein Binding; D019704:Protein Disulfide-Isomerases / Q000378:metabolism*; D017510:Protein Folding; D017451:Receptors, Somatomedin / Q000276:immunology; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D057127:Single-Chain Antibodies / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012995:Solubility
chemical_list: D029968:Escherichia coli Proteins; D017451:Receptors, Somatomedin; D011994:Recombinant Proteins; D057127:Single-Chain Antibodies; D019704:Protein Disulfide-Isomerases; C526648:dsbA protein, E coli; C526649:dsbC protein, E coli