Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
1.1 Introduction of Protein-Protein Interactions . . . . . . . . . . . . . . . . . . . .
1
1.1.1 Significance of Studying Protein-Protein Interactions . . . . .
1
1.1.2 Classification of Protein-Protein Interactions . . . . . . . . . . . .
2
1.1.3 Introduction of Peptide Helix . . . . . . . . . . . . . . . . . . . . . . . . .
3
1.2 History and Current Status of Peptide Drugs . . . . . . . . . . . . . . . . . . . .
5
1.3 Methodology for Stabilizing Peptide Secondary Structures . . . . . . .
8
1.4 Application of Peptide Stabilization Methodology
in the Design of Protein-Protein Interaction Inhibitors . . . . . . . . . . . 15
1.5 The Topic Selection Ideas and Research Focus of This Thesis . . . . . 16
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2 Synthesis of In-Tether Chiral Center Peptides and Their
Biophysical Properties Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
2.2 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
2.2.1 Unnatural Amino Acids Synthesis . . . . . . . . . . . . . . . . . . . . . 27
2.2.2 Solid Phase Peptide Synthesis and Thiol-Ene
Photoreactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
2.2.3 Circular Dichroism Study of Secondary Structures . . . . . . . 29
2.2.4 NMR Study of Peptides’ Secondary Structures . . . . . . . . . . 31
2.2.5 X-Ray Diffraction Analysis of the Crystal Structure . . . . . . 32
2.2.6 Molecular Dynamic Simulations . . . . . . . . . . . . . . . . . . . . . . 35
2.2.7 On the Mechanism of Chirality-Induced Helicity . . . . . . . . 39
2.2.8 Cell Permeability Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
2.2.9 Bioactive Peptide Construction . . . . . . . . . . . . . . . . . . . . . . . 40
2.3 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
2.4 Methods and Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
2.4.1 Reagents and Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
2.4.2 Peptide Purification and Characterization . . . . . . . . . . . . . . . 47
2.4.3 CD Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
2.4.4 NMR Spectroscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
xiii
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
1.1 Introduction of Protein-Protein Interactions . . . . . . . . . . . . . . . . . . . .
1
1.1.1 Significance of Studying Protein-Protein Interactions . . . . .
1
1.1.2 Classification of Protein-Protein Interactions . . . . . . . . . . . .
2
1.1.3 Introduction of Peptide Helix . . . . . . . . . . . . . . . . . . . . . . . . .
3
1.2 History and Current Status of Peptide Drugs . . . . . . . . . . . . . . . . . . . .
5
1.3 Methodology for Stabilizing Peptide Secondary Structures . . . . . . .
8
1.4 Application of Peptide Stabilization Methodology
in the Design of Protein-Protein Interaction Inhibitors . . . . . . . . . . . 15
1.5 The Topic Selection Ideas and Research Focus of This Thesis . . . . . 16
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2 Synthesis of In-Tether Chiral Center Peptides and Their
Biophysical Properties Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
2.2 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
2.2.1 Unnatural Amino Acids Synthesis . . . . . . . . . . . . . . . . . . . . . 27
2.2.2 Solid Phase Peptide Synthesis and Thiol-Ene
Photoreactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
2.2.3 Circular Dichroism Study of Secondary Structures . . . . . . . 29
2.2.4 NMR Study of Peptides’ Secondary Structures . . . . . . . . . . 31
2.2.5 X-Ray Diffraction Analysis of the Crystal Structure . . . . . . 32
2.2.6 Molecular Dynamic Simulations . . . . . . . . . . . . . . . . . . . . . . 35
2.2.7 On the Mechanism of Chirality-Induced Helicity . . . . . . . . 39
2.2.8 Cell Permeability Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
2.2.9 Bioactive Peptide Construction . . . . . . . . . . . . . . . . . . . . . . . 40
2.3 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
2.4 Methods and Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
2.4.1 Reagents and Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
2.4.2 Peptide Purification and Characterization . . . . . . . . . . . . . . . 47
2.4.3 CD Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
2.4.4 NMR Spectroscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
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