Water-Soluble Diketopiperazine Receptors - Selective Recognition of Arginine-Rich Peptides

Abstract

The selective recognition of arginine-rich peptides by diketopiperazine receptors in aqueous solution is presented. The binding properties of the easily prepared receptors were elucidated by on-bead screenings with a combinatorial split-and-mix peptide library.

arginine - combinatorial chemistry - peptides - molecular recognition - two-armed receptors

References

For reviews see:

1a Srivinasan N. Kilburn JD. Curr. Opin. Chem. Biol.  2004,  8:  305 

1b Lavigne JJ. Anslyn EV. Angew. Chem. Int. Ed.  2001,  40:  3118 

2 Loergen JW. Kreutz C. Bargon J. Krattiger P. Wennemers H. Sens. Actuators, B  2004,  in press 

3a Wennemers H. Nold MC. Conza MM. Kulicke KJ. Neuburger M. Chem.-Eur. J.  2003,  9:  442 

3b Conza M. Wennemers H. J. Org. Chem.  2002,  67:  2696 

3c Wennemers H. Conza M. Nold M. Krattiger P. Chem.-Eur. J.  2001,  7:  3342 

4 For a review see: Krebs A. Ludwig V. Boden O. Göbel MW. ChemBioChem  2003,  4:  972 

5

HATU: O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyl-uronium-hexafluorophosphate; EDC: 1-(3-di-methyl-aminopropyl)-3-ethylcarbodiimide hydrochloride.

6

Receptor 1: ¹H NMR (500 MHz, DMSO-d ₆, 22 °C): δ = 12.34 (br s, 4 H, COOH), 8.35 (ψd, J = 9.1 Hz, 4 H, DR-ar), 8.24 (d, J = 7.1 Hz, 2 H, Asp′-NH), 8.19 (d, J = 7.7 Hz, 2 H, Asp-NH), 8.03 (d, J = 6.2 Hz, 2 H, Pro-γNH), 7.93 (ψd, J = 9.1 Hz, 4 H, DR-ar), 7.84 (d, 4 H, J = 9.2 Hz, DR-ar), 7.71 (br s, 2 H, Tyr-NH), 7.09 (d, J = 8.7 Hz, 4 H, Tyr-ar), 6.94 (d, J = 9.3 Hz, 2 H, DR-ar), 6.83 (d, J = 8.7 Hz, 4 H, Tyr-ar), 4.54 (dψt, J = 5.5 Hz, 7.9 Hz, 2 H, Asp-Hα), 4.44 (ψq, J = 6.6 Hz, 2 H, Asp′-Hα), 4.32 (m, 2 H, Pro-Hα), 4.29 (ψq, J = 6.3 Hz, 2 H, Tyr-Hα), 4.17 (m, 2 H, Pro-Hγ), 4.14 (t, J = 5.7 Hz, 4 H, NCH₂CH ₂ O), 3.84 (t, J = 5.5 Hz, 4 H, NCH ₂ CH₂O), 3.64 (dd, J = 5.9 Hz, 11.7 Hz, 2 H, Pro-Hδ), 3.60 (q, J = 7.2 Hz, 4 H, NCH ₂ CH₃), 3.17 (br d, J = 5.0 Hz, 2 H, Pro-Hδ′), 2.89 (m, J = 14.0 Hz, 2 H, Tyr-Hβ), 2.77 (dd, J = 9.0 Hz, 14.5 Hz, 2 H, Tyr-Hβ′), 2.65 (dd, J = 5.1 Hz, 11.2 Hz, 2 H, Asp-Hβ), 2.62 (dd, J = 10.9 Hz, 4.9 Hz, 2 H, Asp′-Hβ), 2.46 (m, 4 H, Asp-Hβ′, Asp′-Hβ′), 2.14 (m, 2 H, Pro-Hβ), 1.87 (m, 2 H, Pro-Hβ′), 1.82 (s, 6 H, COCH₃), 1.18 (t, J = 7.1 Hz, 6 H, NCH₂CH ₃ ). ¹³C NMR (125.6 MHz, DMSO-δ₆, 22 °C): δ = 172.0, 171.9, 171.2, 170.4, 170.1, 169.6, 165.8, 156.9, 156.2, 151.7, 146.9, 142.8, 130.3, 129.7, 126.1, 125.0, 122.5, 114.0, 111.7, 65.2, 58.1, 54.4, 50.4, 49.8, 49.6, 49.2, 46.9, 45.3, 36.6, 36.1, 35.6, 33.1, 22.5, 12.0. MS (ESI): m/z (%) = 842.3 (100) [M - 2H]^2-, 1686.2 (53) [M - H]^-.
Receptor 2: ¹H NMR (500 MHz, DMSO-d ₆, 22 °C): δ = 8.35 (ψd, 4 H, J = 9.0 Hz, DR-ar), 8.27 (d, J = 7.5 Hz, 2 H, Asp-NH), 8.06 (d, J = 6.4 Hz, 2 H, Pro-γNH), 8.16 (d, J = 7.6 Hz, 2 H, Asp′-NH), 7.93 (ψd, 4 H, J = 9.0 Hz, DR-ar), 7.85 (d, 4 H, J = 9.2 Hz, DR-ar), 7.68 (d, J = 8.0 Hz, 2 H, Tyr-NH), 7.09 (d, 4 H, J = 8.6 Hz, Tyr-ar), 6.94 (d, 2 H, J = 9.3 Hz, DR-ar), 6.83 (d, 4 H, J = 8.6 Hz, Tyr-ar), 4.54 (dψt, J = 5.6 Hz, 7.7 Hz, 2 H, Asp-Hα), 4.46 (ψq, J = 6.7 Hz, 2 H, Asp′-Hα), 4.30 (m, 4 H, Tyr-Hα, Pro-Hα), 4.14 (t, J = 5.4 Hz, 6 H, NCH₂CH ₂ O, Pro-Hα), 3.84 (t, J = 5.1 Hz, 4 H, NCH ₂ CH₂O), 3.64 (m, 4 H, Pro-Hδ), 3.60 (q, J = 7.0 Hz, 4 H, NCH ₂ CH₃), 3.17 (br d, J = 9 Hz, 2 H, Pro-Hδ′), 2.88 (dd, J = 6.2 Hz, 14.6 Hz, 2 H, Tyr-Hβ), 2.77 (dd, J = 8.8 Hz, 13.4 Hz, 2 H, Tyr-Hβ′), 2.68 (dd, J = 16.5 Hz, 5.4 Hz, 2 H, Asp-Hβ), 2.64 (dd, J = 16.8 Hz, 5.9 Hz, 2 H, Asp′-Hβ), 2.44 (m, 8 H, COCH ₂ CH₂CO, Asp-Hβ′, Asp′-Hβ′), 2.36 (t, J = 6.4 Hz, 4 H, COCH₂CH ₂ CO,), 2.14 (m, 2 H, Pro-Hβ), 1.86 (m, 2 H, Pro-Hβ′), 1.18 (t, J = 6.9 Hz, 6 H, NCH₂CH ₃ ). ¹³C NMR (125.6 MHz, DMSO-d ₆, 22 °C): δ = 173.9, 171.9, 171.9, 171.6, 171.1, 170.3, 170.0, 165.8, 156.9, 156.2, 151.7, 146.9, 142.8, 130.3, 129.6, 126.2, 125.0, 122.5, 114.0, 111.7, 65.2, 58.1, 54.3, 50.6, 49.7, 49.6, 49.2, 46.9, 45.3, 36.7, 36.0, 35.5, 33.1, 30.0, 29.1, 12.0. MS (ESI): m/z (%) = 900.6 (100) [M - 2H]^2-.

7

TentaGel was purchased from Rapp (Tübingen, Germany).

8 Ohlmeyer MHJ. Swanson RN. Dillard LW. Reader JC. Asouline G. Kobayashi R. Wigler MH. Still WC. Proc. Natl. Acad. Sci. U. S. A.  1993,  90:  10922 

9a Furka . Sebestyén F. Asgedom M. Dibo G. Int. J. Pept. Protein Res.  1991,  37:  487 

9b Lam KS. Salmon SE. Hersh EM. Hruby VJ. Kazmierski WM. Knapp RJ. Nature  1991,  354:  82 

10

AA1-AA3 = Gly, d-Ala, l-Ala, d-Val, l-Val, d-Leu, l-Leu, d-Phe, l-Phe, d-Pro, l-Pro, d-Ser, l-Ser, d-Thr, l-Thr, d-Cys, l-Cys, d-Asp, l-Asp, d-Glu, l-Glu, d-Asn, l-Asn, d-Gln, l-Gln, d-His, l-His, d-Lys, l-Lys, d-Arg, l-Arg.

11 In order to ensure the presence of each library member 3-5 theoretical copies of the library were present in each assay: Burgess K. Liaw AI. Wang NY. J. Med. Chem.  1994,  37:  2985 

12

Disperse Red 1 was chosen as a colored marker since it is know not to bind by itself to peptides, see also ref. 4.

13

Titrations were performed at 25 °C using a Microcal
VP-ITC titration microcalorimeter. Sample solutions were prepared using Milli-Q water. Titrations of Ac-Arg-Arg-Arg-NHPr were performed by adding aliquots of a 5 mM peptide solution to a 0.2 mM receptor solution. The titrations were analyzed using a least squares curve-fitting procedure (Origin^® implemented with the calorimetric setup provided by Microcal).