An experimental approach to probe conformational changes in protein structure using a biotin derivative followed by mass spectrometry [Elektronische Ressource] / vorgelegt von Omid Azimzadeh

Omid Azimzadeh

Sujets

• Biologie
• Gesundheit

Informations

• Publié par: philipps-universitat_marburg
• Publié le: 01 janvier 2008
• Nombre de lectures: 21
• Langue: English
• Poids de l'ouvrage: 5 Mo

Extrait

An experimental approach to probe conformational changes in protein
structure using a biotin derivative followed by mass spectrometry





Dissertation
zur Erlangung des Doktorgrades
der Naturwissenschaften
(Dr. rer. nat.)




dem Fachbereich Biologie
der Philipps-Universität Marburg
vorgelegt von




Omid Azimzadeh
aus Teheran



Marburg/ Lahn 2008

































Vom Fachbereich Biologie der Philipps-Universität Marburg als Dissertation
am angenommen.
Erstgutachter: Prof. Dr. Klaus Lingelbach
Zweitgutachter: Prof. Dr. Uwe G. Maier

Tag der mündlichen Prüfung am:



The following paper was published by the date of the present thesis:

Azim-Zadeh O, Hillebrecht A, Linne U, Marahiel MA, Klebe G, Lingelbach K,
Nyalwidhe J. (2007). Use of biotin derivatives to probe conformational changes in
proteins. J Biol Chem. 282(30):21609-17.






























For my wife Maryam










I Table of Contents


II List of Figures 4
III List of Tables 6
IV List of Abbreviations 7

1. Introduction 8
1.1. Erythrocyte membrane structure 8
1.1.1. Membrane lipids 8
1.1.2. Membrane proteins 8
1.1.3. Erythrocyte surface proteins 10
1.1.4. Membrane transporters and channels 10
1. 2. The membrane of the P. falciparum infected erythrocytes 11
1.2.1. The malaria parasite Plasmodium falciparum 11
1.2.1.1. Parasite Life Cycle 11
1.2.1.2. Alteration of the host plasma membrane 12
1.2.1.3. Novel Permeation Pathways (NPPs) 15
1.3. Biotinylation of proteins 19
1.4. Mass spectrometry 21
1.5. Study of conformational changes in model protein 24
1.5.1. The structure and properties of bovine serum albumin (BSA) 24
1.5.2. The structure and properties of Carbonic anhydrase II (CA II) 28
1.6. The structure and properties of Band III protein (Anion Exchanger 1, AE1) 31
1.7 Objectives 37

2. Materials and Methods 38
2.1. Materials 38
2.1.1. Equipments 38
2.1.2. Disposable Materials 39
2.1.3. Chemicals and reagents 39
1 I Table of Contents

2.1.4. Solutions and buffers 41
2.1.5. Host cells and parasite isolates 44
2.1.6. Antibodies and working concentrations 44
2.17. Software 44
2. Methods 45
2.2.1. Parasite Cultures 45
2.2.2. Biotin labelling of bovine serum albumin and carbonic anhydrase II 45
2.2.3. Biotinylation of erythrocyte membrane protein Band III 46
2.2.4. Affinity purification of biotinylated peptides 46
2.2.5. Gel Electrophoresis (Laemmli, 1970) 47
2.2.6. Western Blot Analysis (Towbin et al., 1979) 47
2.2.7. Sample preparation for mass spectrometry 47
2.2.8. Mass spectrometry analysis and protein identification 49

3. Results 51
3.1. Biotinylation pattern of BSA is saturable 51
3.2. Biotinylated lysine residues in BSA are uniformly distributed in the protein 54
3.3. Not all lysine residues of BSA can be detected by mass spectrometry 55
3.4. The modified lysine residues are identified by MS and MS/MS analysis 58
3.5. Biotinylated peptides can be effectively affinity purified
using streptavidin sepharose beads 60
3.5.1. Affinity purification of intact biotinylated BSA 61
3.5.2. Affinity purification of biotinylated BSA peptides 62
3.6. Biotinylated lysine residues are resistant to trypsin cleavage 64
3.7. Elevated temperatures expose novel lysine residues in the
biotinylation pattern of BSA 65
3.8. Reduction has no effect on the biotinylation pattern of BSA 70
3.9. The biotinylation reaction does not induce structural changes in the
biotinylated protein, as detected by circular dichroism 71
3.10. Involvement of lysine residues in hydrogen bonding may
decrease their capacity to be biotinylated 74
2 I Table of Contents

3.11. Analysis of biotinylated and non-biotinylated CA II by MS 78
3.12. Band III is biotinylated in infected and non-infected erythrocytes 81
3.13. MS analysis identifies Band III 84
3.14. The peaks found in non-biotinylated samples are falsely identified
by database searches as corresponding to a biotinylated peptide 88
3.15. Biotinylated Band III peptides were rarely detected 91
3.16. Biotinylation does not affect the ionization efficiency of peptides 97

4. Discussion 99
4.1. Biotinylated lysine residues can be detected by MS and MS/MS analysis 100
4 2 .The biotinylation of protein is reproducible but incomplete 100
4.3 .The conformational changes are reflected in the biotinylation pattern 103
4.4. The biotinylated lysine residues are resistant to trypsin cleavage 104
4.5. Involvement of lysine residues in H bonding may prevent the biotinylation 104
4.6. Only few biotinylated lysine residues in Band III structure are detected 105
4.7. The biotinylation pattern of Band III is different in RBC and IRBC 107
4.8. Future directions and implications of this study 109

5. Litrature 111
V Summary 125
VI Zusammenfassung 126
Acknowledgements 127
Declaration 128
Appendix 129
3 II List of Figures

II List of Figures

Figure 1. The erythrocyte membrane organization 9
Figure 2. Parasite induced alterations in infected erythrocytes 15
Figure 3. The sulfo-NHS-LC biotin derivative reacts with primary amines
forming an amide bond 21
Figure 4. The comparison of primary structure of HAS and BSA 26
Figure 5. The secondary structure of bovine CA II 29
Figure 6. Proposed topology model for Band III protein with
12-14 transmembrane domains 34
Figure 7. Biotinylation with sulfo-NHS-LC-Biotin increases the mass of peptides
by a specific value 51
Figure 8. Analysis of the mass of BSA after biotinylation using increasing
concentrations of sulfo-NHS-LC-Biotin 52
Figure 9. Effect of the increase in the concentration of sulfo-NHS-LC-biotin
on the biotinylation and mass of BSA 53
Figure 10. Comparison of the detected sequence coverage in biotinylated
and non-biotinylated BSA 56
Figure 11. Comparison of biotinylated and non-biotinylated BSA 59
Figure 12. MS/MS spectra of peptide 1329.694 which was detected in the
biotinylated BSA 60
Figure 13. Schematic representation of the experimental methodology for the
affinity purification of biotinylated intact BSA or biotinylated BSA peptides using streptavidin beads 61
Figure 14. Comparison of bound and unbound fraction of biotinylated BSA 62
Figure 15. Comparison of generated peptides from starting, bound and unbound
fractions of biotinylated BSA 63
Figure 16. Comparison of the biotinylation pattern of BSA after exposure to
different temperatures 66

4 II List of Figures

Figure 17. Sections of the MALDI mass spectra for BSA biotinylated at RT
and after exposure to an elevated temperature of 80°C 67
Figure 18. MS/MS analysis of peptide 1979.09 that is only biotinylated
after exposure to a temperature of 80°C 68
Figure 19. MS/MS analysis of peptide 2810.253 69
Figure 20. Far-UV CD spectra for different samples of BSA 73
Figure 21. Position of biotinylated lysine residues in the primary structure of BSA 75
Figure 22. Analysis of the mass of biotinylated CA II after exposure to different
temperature 78