title: Separation/enrichment of active natural low content protein using protein imprinted polymer.
abstract: We describe a new type of protein-imprinted polymer for separation/enrichment of active natural protein present at a relatively low level in cell extracts, with a cloned bacterial protein as template. In this work, cloned pig cyclophilin 18 (pCyP18) was used as template. The template protein was selectively assembled with assistant recognition polymer chains (ARPCs) from their library, which consists of numerous limited length polymer chains with randomly distributed recognition and immobilizing sites. These assemblies of protein and ARPCs were adsorbed by porous polymeric beads and immobilized by cross-linking polymerization. After removing the template, the synthesized imprinted polymer was used to adsorb authentic pCyP18 from cell extract, and its proportional content was enriched 200 times. The assay of peptidyl-prolyl cis-trans-isomerase (PPIase) activity showed that natural pCyP18 is more active than cloned pCyP18 and, in particular, it is much more sensitive to the suppressant cyclosporine A (CsA).
authors.affiliation: Biochemical Section of Key Laboratory of Functional Polymer Materials, The Ministry of Education of China, Institute of Polymer Chemistry, Chemical School of Nankai University, Tianjin, PR China.
authors.forename: Ruifang
authors.initials: R
authors.lastname: Han
authors.forename: Xiaocui
authors.initials: X
authors.lastname: Xing
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Yi
authors.initials: Y
authors.lastname: Long
authors.forename: Yang
authors.initials: Y
authors.lastname: Sun
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Zhao
authors.forename: Huaifeng
authors.initials: H
authors.lastname: Mi