title: Improving aquaporin Z expression in Escherichia coli by fusion partners and subsequent condition optimization.
abstract: Aquaporin Z (AqpZ), a typical orthodox aquaporin with six transmembrane domains, was expressed as a fusion protein with TrxA in E. coli in our previous work. In the present study, three fusion partners (DsbA, GST and MBP) were employed to improve the expression level of this channel protein in E. coli. The result showed that, compared with the expression level of TrxA-AqpZ, five- to 40-fold increase in the productivity of AqpZ with fusion proteins was achieved by employing these different fusion partners, and MBP was the most efficient fusion partner to increase the expression level. By using E. coli C43 (DE3)/pMAL-AqpZ, the effects of different expression conditions were investigated systematically to improve the expression level of MBP-AqpZ in E. coli. The high productivity of MBP-AqpZ (200 mg/l) was achieved under optimized conditions. The present work provides a novel approach to improve the expression level of membrane proteins in E. coli.
authors.affiliation: Institute of Bioengineering, Department of Chemical and Biochemical Engineering, Zhejiang University, Hangzhou, 310027, China.
authors.forename: Jiazhang
authors.initials: J
authors.lastname: Lian
authors.forename: Shinghua
authors.initials: S
authors.lastname: Ding
authors.forename: Jin
authors.initials: J
authors.lastname: Cai
authors.forename: Danping
authors.initials: D
authors.lastname: Zhang
authors.forename: Zhinan
authors.initials: Z
authors.lastname: Xu
authors.forename: Xiaoning
authors.initials: X
authors.lastname: Wang
mesh_terms: D020346:Aquaporins / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D005822:Genetic Vectors / Q000235:genetics; D015202:Protein Engineering / Q000379:methods*; D011993:Recombinant Fusion Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D020346:Aquaporins; D029968:Escherichia coli Proteins; D011993:Recombinant Fusion Proteins; C106425:aqpZ protein, E coli