A scientist is worried that the mitochondria he is studying are uncoupled. They estimate high rates of the electron transport chain activity by measuring NADH oxidation, high rates of oxygen uptake using a Clark electrode, but very low ATP synthesis in an assay. Explain what is happening in the experiment and assess their analysis – are they right? (10 marks)
Question 2 (Limit 300 words)
A scientist is worried that the protein sample she is working on has misfolded and aggregated. The results of analysis by SDS-PAGE (A), size exclusion chromatography (B), circular dichroism (C) and 1d-NMR (D) are shown below. The void volume of the size exclusion column was 8 ml.
What information can you gather from each of these results below? (8 marks)
What advice can you give to the scientist? (2 marks)
(Turn Over)
Question 3 (Limit 300 words)
(a) What is a specificity pocket (2-3 sentences)? (2 marks)
(b) Consider the hypothetical serine pro-tease below, which shows the specificity pockets. The S1 pocket has a glutamic acid in the bottom, the S2 pocket is small and hydrophobic, and the S1’ pocket is deep and hydrophobic. Suggest a 3 amino acid sequence that this protease could cleave and explain your reasoning (2-3 sentences for each pocket). (6 marks)
Sample Solution
