title: Poly(N-isopropylacrylamide-co-tris-nitrilotriacetic acid acrylamide) for a combined study of molecular recognition and spatial constraints in protein binding and interactions.
abstract: Many biological processes require precise regulation and synergy of proteins, and consequently involve molecular recognition and spatial constraints between biomolecules. Here, a library of poly(N-isopropylacrylamide-co-tris-nitrilotriacetic acid acrylamide) (PNTs) has been synthesized and complexed with Cu(2+) in order to serve as models for investigation of the combined effects of molecular recognition and spatial constraints in biomolecular interactions. The average distance between Cu(2+)-trisNTA binding sites in PNTs polymers was varied from 4.3 to 31.5 nm by adjusting their trisNTA contents. His tag (His6), His-tagged enhanced yellow fluorescent protein (His6-eYFP), and His6-tagged collagenase G (His6-ColG), with sizes ranging from 1 to 11 nm, were used as models to assess whether the binding ability is influenced by a cooperative topology based on molecular recognition interactions with Cu(2+)-trisNTA binding sites, and spatial constraints created by decreasing average distance between trisNTAs. His-tagged molecules bound to all PNTs polymers due to their molecular recognition interaction involving histidines and Cu(2+)-trisNTA pockets, but with a binding ability that was highly modulated by the average distance between the trisNTA binding sites. Small molecular mass molecules (His6) exhibit a high binding ability to all PNTs polymers, whereas his-tagged proteins bind to PNTs efficiently only when the average distance between trisNTA binding sites is larger than the protein dimensions.
authors.affiliation: Department of Chemistry, University of Basel , Klingelbergstrasse 80, Basel 4056, Switzerland.
authors.forename: Juan
authors.initials: J
authors.lastname: Liu
authors.forename: Mariana
authors.initials: M
authors.lastname: Spulber
authors.forename: Dalin
authors.initials: D
authors.lastname: Wu
authors.forename: Renee M
authors.initials: RM
authors.lastname: Talom
authors.forename: Cornelia G
authors.initials: CG
authors.lastname: Palivan
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Meier
mesh_terms: D000180:Acrylic Resins / Q000138:chemical synthesis / Q000737:chemistry*; D017364:Collagenases / Q000737:chemistry* / Q000378:metabolism; D003300:Copper / Q000737:chemistry; D006639:Histidine / Q000737:chemistry; D008164:Luminescent Proteins / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry; D011485:Protein Binding; D013816:Thermodynamics
chemical_list: D000180:Acrylic Resins; D008164:Luminescent Proteins; D009942:Organometallic Compounds; D006639:Histidine; D003300:Copper; D017364:Collagenases