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The first cDNA from lampyridae encoding a glow-worm luciferase from lantern mRNA of Lampyris turkestanicus has been cloned, sequenced, the amino acid sequence predicted, and the sequence reported to GenBank. The cDNA was 1644 base pairs in length and coding a 547-residue protein. The deduced amino acid sequence of the luciferase gene of L. turkestanicus showed 98.7% and 95.8% identity to Lampyris noctiluca and Pyrocoelia rufa, respectively. Phylogenetic analysis further confirmed that the deduced amino acid sequences of L. turkestanicus luciferase gene belong to the same subfamily, Lampyrinae. The cDNA encoding the luciferase of L. turkestanicus was expressed as a 62kDa band in recombinant Escherichia coli and showed green luminescence in the presence of luciferin. Amongst amino acid differences of L. turkestanicus and L. noctiluca (its clade) there are two important substitutions. Signature amino-acid sequences and motifs found in the deduced sequence are CK2-phospho site, ASN-glycosylation, myristoylation site, PKC-phospho site, microbodies C-terminal targeting signal, and AMP-binding domain.

The chemiluminescence characteristics of seven different cumarin derivatives were studied in detail. The fluorescence and chemiluminescence spectra were compared; all cumarins used were found to act as blue fluorescers. The intensity and kinetic parameters for the chemiluminescent systems were evaluated from computer fitting of the resulting intensity-time plots. Among different cumarin derivatives used, 7-amino-4-trifluoromethylcumarin revealed the most promising characteristics as an efficient blue fluorescent emitter.

The chemiluminescence arising from the reaction of bis(2,4,6-trichlorophenyl)oxalate (TCPO) with hydrogen peroxide in the presence of acriflavine has been studied. The relationship between the chemiluminescence intensity and concentrations of TCPO, H2O2, acriflavine and the base sodium salicylate are reported. The kinetic parameters for the peroxyoxalate-chemiluminescence (PO-CL) of acriflavine were evaluated from the computer fitting of the corresponding chemiluminescence intensity-time plots.

The chemiluminescence generated from the reaction of a thermally stable phenylphosphate-substituted dioxetane Lumigen PPD at ambient temperature was studied in DMSO solution. The presence of trivalent metal ions Cr(3+), Ga(3+), Fe(3+) and Al(3+) was found to quench the resulting chemiluminescence dramatically. The system resulted in nice Stern-Volmer plots in the quencher concentration range 1.5 x 10(-4)-1.8 x 10(-3) mol/L. The K(Q) values decreased in the order Cr(3+) > Ga(3+) > Fe(3+) > Al(3+)., (Copyright 2002 John Wiley & Sons, Ltd.)

The quenching effect of triethylamine on strong chemiluminescence of bis-(2,4,6-trichlorophenyl)oxalate-hydrogen peroxide system in the presence of 7-amino-4-trifluoromethylcumarin was studied. The system resulted in a nice Stern-Volmer plot with a kQ value of 1.07 x 10(-3) M(-1), in the quencher concentration range of 1.52 x 10(-4) - 1.36 x 10(-3) M. The linear correlation between the decay rate constant of the resulting chemiluminescence and the quencher concentration was also investigated.

Iranian firefly larvae, Lampyris turkestanicus collected from north of Iran and their luciferin were analyzed by HPLC, TLC, MS and spectroscopic Fourier transform ([FT]-IR, FT-NMR, UV and fluorescence) methods. The results showed that luciferin in L turkestanicus lanterns was the same as in the American firefly, Photinus pyralis and synthetic D-luciferin.