PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 2016307-5 1991 Fluorescence energy transfer (FET) between the donor (fluorescein.PFO or PFOD) and the acceptor (tetramethylrhodamine.PFO or PFOA) was detected by both quenching of donor fluorescence (520 nm) and by enhancement of acceptor fluorescence (575 nm) upon aggregation of labeled cytolysin molecules. Fluorescein 54-65 perforin 1 Homo sapiens 274-283