title: Magnetic resonance imaging detects a specific peptide-protein binding event.
abstract: DOTA was conjugated to the N-terminus of a 12-mer peptide by using standard peptide synthesis chemistry. The peptide, first isolated by phage display, maintained a high affinity for its protein-binding target, Gal-80, even with GdDOTA attached. The high affinity constant (KA = 5 x 105 M-1) combined with the high relaxivity of the resulting GdDOTA-peptide.protein complex (r1bound = 44.8 +/- 1.7 mM-1 s-1) allowed detection of Gal-80 at muM levels using a standard magnetic resonance imaging protocol. This novel peptide-based, binding-activated MRI method could potentially be used to screen a wide variety of biomolecules.
authors.affiliation: Department of Chemistry, The University of Texas at Dallas, P.O. Box 830688, Richardson, Texas 75083, USA.
authors.forename: Luis M
authors.initials: LM
authors.lastname: De León-Rodríguez
authors.forename: Alfonso
authors.initials: A
authors.lastname: Ortiz
authors.forename: Allison L
authors.initials: AL
authors.lastname: Weiner
authors.forename: Shanrong
authors.initials: S
authors.lastname: Zhang
authors.forename: Zoltan
authors.initials: Z
authors.lastname: Kovacs
authors.forename: Thomas
authors.initials: T
authors.lastname: Kodadek
authors.forename: A Dean
authors.initials: AD
authors.lastname: Sherry
mesh_terms: D000595:Amino Acid Sequence; D003287:Contrast Media / Q000737:chemistry*; D005656:Fungal Proteins / Q000737:chemistry / Q000378:metabolism*; D006571:Heterocyclic Compounds / Q000737:chemistry*; D008279:Magnetic Resonance Imaging / Q000379:methods; D009842:Oligopeptides / Q000737:chemistry / Q000378:metabolism*; D009942:Organometallic Compounds / Q000737:chemistry*; D011485:Protein Binding; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins
chemical_list: D003287:Contrast Media; D005656:Fungal Proteins; C055002:GAL80 protein, S cerevisiae; D006571:Heterocyclic Compounds; D009842:Oligopeptides; D009942:Organometallic Compounds; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; C050823:gadolinium 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetate