title: A bifunctional molecule as an artificial flavin mononucleotide cyclase and a chemosensor for selective fluorescent detection of flavins.
abstract: Flavins, comprising flavin mononucleotide (FMN), flavin adenine dinucleotide (FAD), and riboflavin (RF, vitamin B(2)), play important roles in numerous redox reactions such as those taking place in the electron-transfer chains of mitochondria in all eukaryotes and of plastids in plants. A selective chemosensor for flavins would be useful not only in the investigation of metabolic processes but also in the diagnosis of diseases related to flavins; such a sensor is presently unavailable. Herein, we report the first bifunctional chemosensor (PTZ-DPA) for flavins. PTZ-DPA consists of bis(Zn(2+)-dipicolylamine) and phenothiazine. Bis(Zn(2+)-dipicolylamine) (referred to here as XyDPA) was found to be an excellent catalyst in the conversion of FAD into cyclic FMN (riboflavin 4',5'-cyclic phosphate, cFMN) under physiological conditions, even at pH 7.4 and 27 degrees C, with less than 1 mol % of substrate. Utilizing XyDPA's superior function as an artificial FMN cyclase and phenothiazine as an electron donor able to quench the fluorescence of an isoalloxazine ring, PTZ-DPA enabled selective fluorescent discrimination of flavins (FMN, FAD, and RF): FAD shows ON(+), FMN shows OFF(-), and RF shows NO(0) fluorescence changes upon the addition of PTZ-DPA. With this selective sensing property, PTZ-DPA is applicable to real-time fluorescent monitoring of riboflavin kinase (RF to FMN), alkaline phosphatase (FMN to RF), and FAD synthetase (FMN to FAD).
authors: Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 151-747, Korea.
authors: Hyun-Woo
authors: HW
authors: Rhee
authors: So Jung
authors: SJ
authors: Choi
authors: Sang Ho
authors: SH
authors: Yoo
authors: Yong Oh
authors: YO
authors: Jang
authors: Hun Hee
authors: HH
authors: Park
authors: Rosa María
authors: RM
authors: Pinto
authors: José Carlos
authors: JC
authors: Cameselle
authors: Francisco J
authors: FJ
authors: Sandoval
authors: Sanja
authors: S
authors: Roje
authors: Kyungja
authors: K
authors: Han
authors: Doo Soo
authors: DS
authors: Chung
authors: Junghun
authors: J
authors: Suh
authors: Jong-In
authors: JI
authors: Hong
mesh_terms: D000588:Amines / Q000737:chemistry; D040761:Biomimetic Materials / Q000737:chemistry* / Q000378:metabolism; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D005486:Flavin Mononucleotide / Q000032:analysis / Q000378:metabolism; D005415:Flavins / Q000032:analysis*; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000032:analysis / Q000737:chemistry; D008163:Luminescent Measurements; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D019761:Phosphorus-Oxygen Lyases / Q000378:metabolism*; D010848:Picolinic Acids / Q000737:chemistry; D015032:Zinc / Q000737:chemistry
chemical_list: C501847:2,2'-dipicolylamine; D000588:Amines; D005415:Flavins; D005456:Fluorescent Dyes; D009942:Organometallic Compounds; D010848:Picolinic Acids; D005486:Flavin Mononucleotide; D019761:Phosphorus-Oxygen Lyases; C111330:FMN cyclase; D015032:Zinc