title: Human serum albumin-benzo[a]pyrene anti-diol epoxide adduct structure elucidation by fluorescence line narrowing spectroscopy.
abstract: Cryogenic (4-10 K) laser-induced vibrationless ground state and vibronic excited state fluorescence emission spectra of the adducts resulting from reaction in vitro of human serum albumin and the carcinogen (+-)-r-7,t-8-dihydroxy-c-9,c-10-epoxy-7,8,9,10- tetrahydrobenzo[a]-pyrene were recorded in order to determine the structures formed. Comparison of these fluorescence line-narrowed (FLN) spectra to those obtained from BaP-7,8,9,10- tetrahydrotetrols, synthetic N-t-BOC-alaninate ester, and N tau- and N pi-histidine amine anti-BaPDE adducts revealed that a mixture of adduct types are formed with the protein. Extensive dialysis of the adducted protein simplified the FLN spectrum, causing it to become nearly identical to the FLN spectrum obtained from the stable peptide adduct. Comparison of the FLN spectra of the synthetic histidine adducts to those obtained from peptide adducts isolated from enzymic digestion of the adducted protein indicated that only one of the imidazole nitrogens is the nucleophile which forms a stable adduct with anti-BaPDE. The FLN studies confirm that N tau-histidine adducts are formed between human serum albumin and the C-10 position of anti-BaPDE.
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology, Cambridge 02139.
authors.forename: B W
authors.initials: BW
authors.lastname: Day
authors.forename: M M
authors.initials: MM
authors.lastname: Doxtader
authors.forename: R H
authors.initials: RH
authors.lastname: Rich
authors.forename: P L
authors.initials: PL
authors.lastname: Skipper
authors.forename: K
authors.initials: K
authors.lastname: Singh
authors.forename: R R
authors.initials: RR
authors.lastname: Dasari
authors.forename: S R
authors.initials: SR
authors.lastname: Tannenbaum
mesh_terms: D015123:7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide / Q000737:chemistry*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002851:Chromatography, High Pressure Liquid; D004247:DNA / Q000737:chemistry*; D018736:DNA Adducts; D016172:DNA Fingerprinting; D006639:Histidine / Q000737:chemistry; D006801:Humans; D007834:Lasers; D012709:Serum Albumin / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D014732:Vibration
chemical_list: D018736:DNA Adducts; D012709:Serum Albumin; C043931:benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide-DNA; D006639:Histidine; D015123:7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide; D004247:DNA