title: Click Grafting of Alkyne-containing Vinyl Polymers onto Biosynthesized Extracellular Matrix Protein Containing Azide Functionality and Adhesion Control of Human Umbilical Vein Endothelial Cells.
abstract: In vivoincorporation of a phenylalanine (Phe) analogue,p-azidophenylalanine (p-N3Phe) into an artificial extracellular matrix protein (aECM-CS5-ELF) was accomplished using a bacterial expression host that harbors the mutant phenylalanyl-tRNA synthetase (PheRS) with an enlarged binding pocket, in which the Ala294Gly/Thr251Gly mutant PheRS (PheRS**) was expressed under the control of T7 promoters. In this study, biosynthesized aECM-CS5-ELF containingp-N3Phe (aECM-CS5-ELF-N3) was coupled with alkyne-containing vinyl polymers prepared via controlled radical polymerization of three vinyl monomers, (styrene, acrylamide, andN-isopropylacrylamide) using a trithiocarbonate as the RAFT agent. Grafting of the vinyl polymers onto the aECM was accomplished via a copper-catalyzed alkyne-azide click reaction. The lower critical transition temperature (LCST) was evaluated, as well as the solubility in aqueous and organic media, which are dependent on the incorporation ratio ofp-N3Phe and species of graft chains, in which the LCST behavior was altered remarkably when poly(N-isopropylacrylamide) moieties were attached as side chains. Circular dichroism measurements indicate conformational change was not induced by the grafting. Specific adhesion of human umbilical vein endothelial cells (HUVECs) onto the aECM-CS5-ELF-N3-graft-poly(N-isopropylacrylamide) composite surface and subsequent temperature-sensitive detachment were also demonstrated.
authors: Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan, Telephone: +81-52-735-7159;
authors: Tomoki
authors: T
authors: Yamada
authors: Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan, Telephone: +81-52-735-7159;
authors: Akinori
authors: A
authors: Takasu
keywords: T7 expression system; alkyne-containing vinyl polymer; artificial extracellular matrix protein (aECM); click reaction; in vivo incorporation; p-azidophenylalanine; reversible addition and fragmentation chain-transfer (RAFT) radical polymerization