title: Analysis of close proximity quenching of phosphorescent metalloporphyrin labels in oligonucleotide structures.
abstract: Quenching of phosphorescent platinum(II) and palladium(II) coproporphyrin (MeCP) labelled oligonucleotides was investigated. Strong hybridization-specific quenching was observed in duplex DNA structures with a variety of quenchers and with two identical porphyrin labels when in close proximity. Classical resonance energy transfer mechanism was ruled out, since quenching did not correlate with spectral overlaps and lifetime changes were insignificant. Quenching of MeCP by the free quenchers in solution revealed that porphyrin-porphyrin quenching is predominantly static while other dyes quench dynamically. The results suggest that the quenching in DNA duplex proceeds via direct contact.
authors: Biochemistry Department/ABCRF, Cavanagh Pharmacy Building, University College Cork, Cork, Ireland.
authors: M
authors: M
authors: Burke
authors: P J
authors: PJ
authors: O'Sullivan
authors: G V
authors: GV
authors: Ponomarev
authors: D V
authors: DV
authors: Yashunsky
authors: D B
authors: DB
authors: Papkovsky
mesh_terms: D001483:Base Sequence; D002623:Chemistry Techniques, Analytical / Q000379:methods; D004247:DNA / Q000737:chemistry*; D049408:Luminescent Agents / Q000494:pharmacology*; D008163:Luminescent Measurements / Q000295:instrumentation / Q000379:methods*; D008665:Metalloporphyrins / Q000737:chemistry*; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D015345:Oligonucleotide Probes / Q000737:chemistry; D009841:Oligonucleotides / Q000737:chemistry*; D010165:Palladium / Q000737:chemistry; D010984:Platinum / Q000737:chemistry; D011166:Porphyrins / Q000737:chemistry
chemical_list: D049408:Luminescent Agents; D008665:Metalloporphyrins; D015345:Oligonucleotide Probes; D009841:Oligonucleotides; D011166:Porphyrins; D010984:Platinum; D010165:Palladium; D004247:DNA