1. XXXXXXXXXXXXXXXXXXXA doctor from Cairo, Egypt is perplexed by two twin infants that he is treating for deficiencies in energy production.   He has many theories on what could be the issue, but he wants you to help. He presented their case to your lab. You sequence these infants DNA and try to uncover what metabolic problem they may have that is causing this energy-deficient illness they have.

1. (10 points) You characterize the enzymes for glycolysis, PDH, and TCA cycle and everything seems fine, except for one thing: you discover that these infants have a very strange pathway never discovered before. This pathway takes oxaloacetate from the body and branches it into a pathway that breaks it in down into seemingly non-biologically relevant intermediates. Why could this explain the energy deficiency the Egyptian doctor discovered? (50 words max).

ANSWER:

2. (10 points) You discover that the enzyme that controls this weird oxaloacetate pathway is very similar to Pyruvate Dehydrogenase. Additionally, this pathway can be regulated by reversible covalent modification very similar to that of PDH. These infants have a problem with this regulation, but if this regulation was normal, how could you regulate this weird pathway to solve their problem? Make sure you address ALL possible ways you can regulate, with the knowledge that this is very similar to PDH. (50 words max)

ANSWER:

3. (8 points) You also discover another problem in the infants: a key enzyme responsible for the production of Coenzyme Q (i.e. Ubiquinone) is hugely mutated to work very, very slowly.   This causes very low levels of Coenzyme Q in the infants. Why could this also explain their energy-production problem? (40 words max).

ANSWER:

4. (8 points) You email the doctor and he asks if it is possible to just add Coenzyme Q in the diet if the infant twins. Why may this work, in theory, but why might this be a problem to actually do in the body? Consider the structure of Coenzyme Q and where it is located in the mitochondria? (30 words max).

ANSWER:

explain how a typical digestive enzyme is secreted starting from the time the ribosome starts translating the mRNA of the gene encoding the digestive enzyme

How does temperature and pH affect the ability of an enzyme to bind substrate? and what specific changes occur to the structure of an enzyme when it is boiled?

Glycolysis and gluconeogenesis are opposite pathways. What are three different ways that the pathways are kept from canceling each other out?

Discuss whether glucagon and epinephrine act in the same way in liver, muscle and heart cells in terms of their effects on glycolysis and gluconeogenesis

Approximately how many net molecules of ATP are used or generated by gluconeogenesis as compared to net ATP used or generated by glycolysis?

Of the three regulated steps of the glycolysis pathway, one is unusual. Which step is unusual as a regulated step, and what is unusual about it?

Basically what would be the effect of using O2 instead of NAD+ in glycolysis? Is NAD+ more or less favorable to use in this pathway?

Why does ATP yield vary in cellular respiration (think about how NADH from glycolysis enters mitochondira)?