ACS BIOCHEMISTRY FINAL EXAM STUDY
GUIDE
1. pI (isoelectric point)
Answer pH at which the protein has no net charge.
2. pH
Answer Measure of the acidity or basicity of a solution.
3. pKa
Answer The pH at which half of a given species is deprotonated.
4. Net charge of proteins
Answer Depends on solution pH relative to pKa values.
5. Primary structure
Answer Amino acid sequence of a protein.
6. Secondary structure
Answer Alpha helices and beta sheets in proteins.
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,7. Tertiary structure
Answer 3D folding of a protein, involving hydrophobic core, H-bonds, and salt bridges.
8. Quaternary structure
Answer Assembly of multiple polypeptides into a functional protein.
9. Peripheral proteins
Answer Loosely attached to membranes by ionic/H-bond interactions.
10. Integral proteins
Answer Proteins that span the membrane, often with hydrophobic helices.
11. X-ray crystallography
Answer Determines 3D structure without using electromagnetic radiation directly.
12. NMR spectroscopy
Answer Uses electromagnetic radiation (radio waves) to probe protein structure.
13. UV-Vis spectroscopy
Answer Detects aromatic residues that absorb at approximately 280 nm.
14. IR spectroscopy
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, Answer Measures bond vibrations using electromagnetic radiation.
15. Mass spectrometry
Answer Measures molecular weight of compounds, not using electromagnetic radiation.
16. Dialysis
Answer Separates small molecules from proteins via a semi-permeable membrane.
17. Size exclusion chromatography
Answer Technique where larger proteins elute first.
18. Ion-exchange chromatography
Answer Separates proteins by charge; proteins bind based on pI.
19. SDS-PAGE
Answer Technique that separates proteins by size, with smaller proteins migrating faster.
20. Km
Answer Substrate concentration at which the reaction rate is half of Vmax.
21. Vmax
Answer Maximum rate of an enzyme-catalyzed reaction.
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, 22. Competitive inhibitor
Answer Increases Km without changing Vmax.
23. Non-competitive inhibitor
Answer Decreases Vmax without changing Km.
24. Uncompetitive inhibitor
Answer Decreases both Km and Vmax.
25. Transition State Analog
Answer Molecules that mimic the high-energy transition state and bind enzymes tightly.
26. Michaelis-Menten plot
Answer A hyperbolic curve representing the rate of enzyme reactions.
27. Lineweaver-Burk plot
Answer A double reciprocal linear plot (1/V vs. 1/[S]).
28. Carbonic anhydrase
Answer Enzyme that uses Zn2+ to activate water for nucleophilic attack.
29. Serine protease
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GUIDE
1. pI (isoelectric point)
Answer pH at which the protein has no net charge.
2. pH
Answer Measure of the acidity or basicity of a solution.
3. pKa
Answer The pH at which half of a given species is deprotonated.
4. Net charge of proteins
Answer Depends on solution pH relative to pKa values.
5. Primary structure
Answer Amino acid sequence of a protein.
6. Secondary structure
Answer Alpha helices and beta sheets in proteins.
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32
,7. Tertiary structure
Answer 3D folding of a protein, involving hydrophobic core, H-bonds, and salt bridges.
8. Quaternary structure
Answer Assembly of multiple polypeptides into a functional protein.
9. Peripheral proteins
Answer Loosely attached to membranes by ionic/H-bond interactions.
10. Integral proteins
Answer Proteins that span the membrane, often with hydrophobic helices.
11. X-ray crystallography
Answer Determines 3D structure without using electromagnetic radiation directly.
12. NMR spectroscopy
Answer Uses electromagnetic radiation (radio waves) to probe protein structure.
13. UV-Vis spectroscopy
Answer Detects aromatic residues that absorb at approximately 280 nm.
14. IR spectroscopy
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32
, Answer Measures bond vibrations using electromagnetic radiation.
15. Mass spectrometry
Answer Measures molecular weight of compounds, not using electromagnetic radiation.
16. Dialysis
Answer Separates small molecules from proteins via a semi-permeable membrane.
17. Size exclusion chromatography
Answer Technique where larger proteins elute first.
18. Ion-exchange chromatography
Answer Separates proteins by charge; proteins bind based on pI.
19. SDS-PAGE
Answer Technique that separates proteins by size, with smaller proteins migrating faster.
20. Km
Answer Substrate concentration at which the reaction rate is half of Vmax.
21. Vmax
Answer Maximum rate of an enzyme-catalyzed reaction.
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, 22. Competitive inhibitor
Answer Increases Km without changing Vmax.
23. Non-competitive inhibitor
Answer Decreases Vmax without changing Km.
24. Uncompetitive inhibitor
Answer Decreases both Km and Vmax.
25. Transition State Analog
Answer Molecules that mimic the high-energy transition state and bind enzymes tightly.
26. Michaelis-Menten plot
Answer A hyperbolic curve representing the rate of enzyme reactions.
27. Lineweaver-Burk plot
Answer A double reciprocal linear plot (1/V vs. 1/[S]).
28. Carbonic anhydrase
Answer Enzyme that uses Zn2+ to activate water for nucleophilic attack.
29. Serine protease
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