title: Novel fluorescent sensing system for alpha-fructosyl amino acids based on engineered fructosyl amino acid binding protein.
abstract: A novel fluorescent sensing system for alpha-glycated amino acids was created based on fructosyl amino acid binding protein (FABP) from Agrobacterium tumefaciens. The protein was found to bind specifically to the alpha-glycated amino acids fructosyl glutamine (Fru-Gln) and fructosyl valine (Fru-Val) while not binding to epsilon-fructosyl lysine. An Ile166Cys mutant of FABP was created by genetic engineering and modified with the environmentally sensitive fluorophore acrylodan. The acrylodan-conjugated mutant FABP showed eight-fold greater sensitivity to Fru-Val than the unconjugated protein and could detect concentrations as low as 17 nM, making it over 100-fold more sensitive than enzyme-based detection systems. Its high sensitivity and specificity for alpha-substituted fructosyl amino acids makes the new sensing system ideally suited for the measurement of hemoglobin A1c (HbA1c), a major marker of diabetes.
authors.affiliation: Department of Biotechnology, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan.
authors.forename: Akane
authors.initials: A
authors.lastname: Sakaguchi
authors.forename: Stefano
authors.initials: S
authors.lastname: Ferri
authors.forename: Wakako
authors.initials: W
authors.lastname: Tsugawa
authors.forename: Koji
authors.initials: K
authors.lastname: Sode
mesh_terms: D000596:Amino Acids / Q000032:analysis* / Q000737:chemistry; D015374:Biosensing Techniques; D002352:Carrier Proteins; D005453:Fluorescence; D005632:Fructose / Q000737:chemistry*; D015202:Protein Engineering; D013379:Substrate Specificity
chemical_list: D000596:Amino Acids; D002352:Carrier Proteins; D005632:Fructose