10.1021/ac051151t.s001
Chikashi Nakamura
Chikashi
Nakamura
Yasuhiro Inuyama
Yasuhiro
Inuyama
Hiroki Goto
Hiroki
Goto
Ikuo Obataya
Ikuo
Obataya
Nao Kaneko
Nao
Kaneko
Noriyuki Nakamura
Noriyuki
Nakamura
Noriaki Santo
Noriaki
Santo
Jun Miyake
Jun
Miyake
Dioxin-Binding Pentapeptide for Use in a
High-Sensitivity On-Bead Detection Assay
American Chemical Society
2005
dioxin binding peptides
peptide beads
PCB
acid
dioxin detection method
LDQ
dioxin concentrations
NBD
FLDQI
FLDQV
peptide C terminus
2005-12-01 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Dioxin_Binding_Pentapeptide_for_Use_in_a_High_Sensitivity_On_Bead_Detection_Assay/3253726
The purpose of this study is to develop a dioxin detection
method using a short peptide alternative to an immunoantibody. A full peptide library consisting of 2.5 million
possible amino acid combinations was constructed by a
solid-phase split synthesis approach using 19 natural
amino acids. The peptide beads were subjected to a
competitive binding assay between 2,3,7-trichlorodibenzo-<i>p</i>-dioxin and <i>N</i>-NBD-3-(3‘,4‘-dichlorophenoxy)-1-propylamine (NBD-DCPPA) in a buffer containing 20% 1,4-dioxane. Two almost identical pentapeptides, FLDQI and
FLDQV, that could bind dioxin were screened from the
combinatorial library. NBD-DCPPA and the peptide synthesized on resin beads could be utilized to determine
dioxin concentrations. The fluorescence intensity of the
beads was measured using fluorescence microscopy to
make a calibration curve for the dioxin concentrations.
2,3,7,8-Tetrachlorodibenzo-<i>p</i>-dioxin (2,3,7,8-TeCDD)
could also detected in the presence of 30% 1,4-dioxane.
To optimize the peptide sequence, a one-amino acid-substituted library was prepared using amino acids
including nonnatural amino acids. The internal amino
acids, LDQ, could not be substituted by any other amino
acids. This result indicates that these three side chains
are essential to recognize dioxins. The peptide C terminus
substituted by phenylglycine showed a 10 times lower
detection limit of 2,3,7,8-TeCDD of 150 pM (50 pg/mL)
than the original sequence FLDQV. The cross reactivity
of the dioxin binding peptides including the secondary
derivatives was investigated. Some polycyclic aromatic
hydrocarbons bound to the peptide beads, but nonchlorinated dibenzo-<i>p</i>-dioxin and PCB did not. From these
results, we demonstrate the potential of short peptides
as a practical sensor material targeting low molecular
weight compounds such as dioxin.