1. Which enzyme uses general acid-base catalysis and or covalent catalysis mechanisms to hydrolyze peptidoglycan?

A. Enolase

B. lysozyme

C. chymotrypsin

D. pepsin

E. B-lactamase

2. the HIV protease enzyme uses a general acid-base catalysis mechanism to cleave viral polypeptides but does not use a covalent catalysis. This enzyme functions optimally in the pH range of 4-6. Due to the specific amino acids involved in this catalysis, HIV protease is a member of which subclass of proteases?

A. Metalloproteases

B. Serine proteases

C. aspartyl proteases

D. cysteine proteases

E. lysine proteases

3. If chemical reactions will eventually reach an equilibrium state, what is the purpose of enzymes in a biological system?

A. Enzymes are consumed to speed up chemical reactions

B. Enzymes speed up chemical reactions without being used up in the process

C. Enzymes slow down chemical reactions

D. Enzymes alter the equilibrium state between reactants and products

E. enzymes prevent the formation of unstable reaction intermediates

Two of the facts which differentiate lipids and carbohydrates from amino acids are that, amino acids can neither be stored nor excreted.

true

false

A baby got sick a few weeks after birth and test results show that the baby had higher than normal levels of the amino acid phenylalanine. Which of the following best describes the baby's probable diagnosis?

Maple syrup disease is largely cause by a defect in the biosynthesis of branched-chain amino acids such as isoleucine.

True

False

Individuals with defects in ammonia clearance tend to suffer neurological problems due to influx of calcium ions into the brain.

True

False

Uridylylation of PII stimulates the formation of glutamine from glutamate.

True

False

It can be useful to analyze the steps of glycolysis with respect to the four basic types of enzymes required by this central catabolic pathway and to consider whether each enzyme produces or harvests the energy of an activated carrier.

For each step of glycolysis (see Figure 13–5 or Panel 13–1), A) indicate which type of enzyme (of the four listed below and in Table 13–1 is required—or ‘other’). B) Indicate whether an activated energy carrier is involved, and, if so, how. C) Describe the chemical changes that occur between the substrates and products of each step. Enzyme types: kinase, isomerase, mutase, dehydrogenase

Step 1 enzyme ___________

Step 2 enzyme ___________

Step 3 enzyme ___________

Step 4 enzyme ___________

Step 5 enzyme ___________

Step 6 enzyme ___________

Step 7 enzyme ___________

Step 8 enzyme ___________

Step 9 enzyme ___________

Step 10 enzyme ___________

Do you expect the cell to produce more ATP from one glucose molecule or from one fatty acid molecule? Justify your answer by describing the chemical structure, the relative oxidation level of the carbons, and how each feeds into cell respiration.

In step 7 of the citric acid cycle, fumarase catalyzes the addition of a water molecule to a carbon–carbon double bond (see Panel 13­–2). Can this be considered an oxidation reaction? Explain your answer.

Two amino acids are either not a standard alpha- amino acid or in the S configuration. Which
residues are they, and how are they different? Illustrate your reasoning with chemical
structures

Which of the following is required for an insertion sequence element in E. coli to be able to transpose?

Which type of deletions and/or insertion would not lead to frameshift mutations?

All of the following are requirements of a bacterial cloning vector EXCEPT:

Using Table 1 above again, determine the approximate frequency of the Lw allele in the population:

Pick a protein of interest.->insulin

Use the Blast tool to find protein homologs of your protein and submit blast search.

Use the multalign tool to align five of the homologs and submit alignment.

Identify conserved amino acids and regions of homology.

Find a PDB for your protein or one of the homologs. If your protein has not been examined structurally. (Start Again)

Use Jmol to evaluate your proteins 3D structure and answer the following questions.

How many subunits in your protein?

Does your protein have any cofactors or coenzymes?

How many amino acids residues in one of the subunits of your protein?

How many amino acids interact at the interface of the subunits of your protein?

Does your protein have an active site or ligand binding domain and what are the key amino in that region.  

Cation-exchange chromatography is a popular technique for separating and purifying proteins. This is very similar to the separation purification of the mixture of amino acids you observed in Prac 3. You are asked to purify an enzyme with a pI of 6.5 from a mixture of different proteins You are provided with the following:

• A column packed with cation-exchange resin

• Phosphate buffer at pH 2.6

• Citrate buffer at pH 3.4

• Tris-HCl buffer at pH 8.2

• Sodium hydroxide at pH 12.0

• Pipettes and consumables such as test tubes and beakers

• 10 mL of a protein mixture (1 mg/mL) in citrate buffer at pH 3.4

Questions:

(1) Which buffer would you use to equilibrate your column?

(2) Design a purification procedure describing the loading of the sample onto the column, the sequential addition of buffers and the collection of elution fractions. (You must clearly indicate which buffer you would use for each elution step and the number of fractions you are going to collect.

(3) How would you determine which fraction contained your enzyme of interest?

(4) How would you determine the concentration of the enzyme in the fractions assuming that the enzyme was the only protein present in the fractions.

Read the description and choose the term that matches from the options in the list.

Nucleotide, Hydrolysis, Lipid, Nucleophile, Enzyme, protein, Carbohydrate, nucleoside, Fatty acids, Saponification, Electrophile, peptide, Condensation reaction

Question 24

What is the fate of lactate following exercise cessation?

Question 30

Which of the following will decrease the most—as a percentage of its resting concentration--during an all-out 100-meter dash (lasting about 10 seconds)?

Question 31

What would the effects of a month long high-protein, high-fat diet, low carbohydrate diet be on athletic performance during a marathon? Assume that the person will run the majority of the marathon at >80% VO2peak and will likely run the last few miles at 90% VO2peak:

Question 32

A person accidentally ingests a substance that renders the mitochondrial electron transport chain non-functional. The following is true:

Question 33

You are training a 400-meter running athlete who states she is taking a supplement to increase the bioavailability and activity of phosphoglucoisomerase (a glycolysis pathway enzyme) to boost her race performance. What is the effect you expect?