Table of contents

1. Introduction to Biochemistry4h 34m
2. Water3h 23m
3. Amino Acids8h 10m
4. Protein Structure10h 4m
5. Protein Techniques14h 5m
6. Enzymes and Enzyme Kinetics13h 38m
7. Enzyme Inhibition and Regulation 8h 42m
8. Protein Function 9h 41m
9. Carbohydrates7h 49m
10. Lipids5h 49m
11. Biological Membranes and Transport 6h 37m
12. Biosignaling9h 45m
Review 1: Nucleic Acids, Lipids, & Membranes2h 47m
Review 2: Biosignaling, Glycolysis, Gluconeogenesis, & PP-Pathway3h 12m
Review 3: Pyruvate & Fatty Acid Oxidation, Citric Acid Cycle, & Glycogen Metabolism2h 26m
Review 4: Amino Acid Oxidation, Oxidative Phosphorylation, & Photophosphorylation1h 48m

4. Protein Structure

Altering Primary Protein Structure

Biochemistry

4. Protein Structure

Altering Primary Protein Structure

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Multiple Choice

Patients with sickle-cell anemia disease have a point mutation leading to a single amino acid substitution in the hemoglobin protein, causing it to alter its shape/function. Which amino acid substitution most likely causes the disease?

Ser to Thr

Arg to Lys

Val to Leu

Glu to Val

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Verified step by step guidance

Understand the context: Sickle-cell anemia is caused by a mutation in the hemoglobin protein, specifically in the beta-globin chain.

Identify the mutation: The disease is caused by a point mutation where the amino acid glutamic acid (Glu) is replaced by valine (Val) at the sixth position of the beta-globin chain.

Consider the properties of the amino acids: Glutamic acid is a polar, negatively charged amino acid, while valine is a nonpolar, hydrophobic amino acid. This change affects the solubility and structure of hemoglobin.

Analyze the impact of the substitution: The substitution of Glu to Val leads to the formation of hemoglobin S (HbS), which causes the hemoglobin molecules to stick together, forming fibers that distort red blood cells into a sickle shape.

Conclude the effect: The sickle-shaped cells can block blood flow in small vessels, leading to the symptoms of sickle-cell anemia, such as pain and organ damage.