Term
| Describe 15. Does 2,3 BPG shift hemoglobin's curve to left or right?the nature of the peptide bond. |
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Definition
| Short polymer of amino acids |
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Term
| By convention, how do we always write proteins? |
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Definition
Left to right,
Begin w/ free -NH group and end w/ free -CO2 group |
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Term
| 1. What is the largest amino acid? |
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Definition
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Term
| What is the smallest amino acid? |
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Definition
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Term
| Which 9 amino acids can participate in H bonds? ( DONOR OR ACCEPTOR) |
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Definition
a. Tyrosine
b. Tryptophan
c. Arginine
d. Histidine
e. Glutamic Acid
f. Aspartic Acid
g. Serine
h. Threonine
i. Glutamine/Asparginine |
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Term
| What five amino acids can participate in ionic bonds? |
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Definition
a. Aspartic Acid
b. Glutamic Acid
c. Lysine
d. Arginine
e. Histidine |
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Term
| Which seven amino acids are considered to be completely nonpolar/hydrophobic? |
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Definition
a. Glycine
b. Alanine
c. Valine
d. Isoleucine
e. Leucine
f. Proline
g. Methionine
h. Phenylalanine
i. Tryptophan |
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Term
| What is the only covalent bond that participates in tertiary/quaternary structure? What amino acid forms it? Under what conditions? |
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Definition
| Disulfide bonds, formed by cysteine groups that are oxidized into one group. |
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Term
| What force “causes” a protein to fold? |
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Definition
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Term
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Definition
| independent functional units of the protein 100–200 amino acids long - encoded by a specific DNA sequence (exon) |
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Term
| What is the difference between homotypic and heterotypic quaternary structures? |
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Definition
a. Homotypic- identical subunits
b. Heterotypic- association between subunits of different structures |
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Term
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Definition
| independent functional units of the protein 100–200 amino acids long - encoded by a specific DNA sequence (exon) |
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Term
| What is the difference between homotypic and heterotypic quaternary structures? |
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Definition
a. Homotypic- identical subunits
b. Heterotypic- association between subunits of different structures |
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Term
| Can any R group of the 20 a.a bind O2 |
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Definition
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Term
| What metal do we use to bind oxygen? |
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Definition
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Term
| What redox state does iron have to be to bind oxygen? |
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Definition
| Fe+2, ferrous, binds 02 reversibly |
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Term
| Why isnt it advantageous to have free iron in our blood to bind oxygen? |
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Definition
| Hydroxyl radicals(damaging to cell membranes and DNA |
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Term
| What do we callmyoglobin that has iron in the incorrect redox state? |
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Definition
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Term
| How many interactions does Fe make with heme? |
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Definition
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Term
| What is the function of myoglobin? |
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Definition
| Oxygen storage of protein muscle |
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Term
| 12. What is meant by proximal vs distal Histidine when referring to myoglobin? |
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Definition
Proximal histidine has an Imidazole Nitrogen that is close enough to bond directly to the Fe2+ atom
b. Distal histidine is important for allowing binding of O2 to the Fe2+ atom |
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Term
| What are the names of the subunits of hemoglobin? |
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Definition
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Term
| 2. Are the closest contacts between the two alpha or two beta subunits in hemoglobin, or between an alpha and beta subunit? |
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Definition
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Term
| 3. Draw the oxygen dissociation curve for hemoglobin. What is its shape? What are the units on the axis? |
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Definition
[image]
b. More S- shaped sigmoidal
c. Read R to L because we are talking about how much Oxygen we are giving up
d. Read thru the tissues to see how much Oxygen has been delivered. |
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Term
| How much more oxygen is released by hemoglobin to the tissues under exercise conditions compared to rest? |
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Definition
Rest:20-25%\
Excercise: 60-100% |
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Term
| Define cooperative binding in terms of oxygen binding to hemoglobin |
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Definition
| a. filling of the first O2 site increases the affinity of the remaining sites for O2 or losing a few O2’s makes it easier to lose more. |
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Term
| What is the R state of hemoglobin? Does it have less or greater affinity for oxygen? |
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Definition
a. (relaxed) state corresponds to oxygenated form
b. Higher Affinity |
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Term
| What is the T state of hemoglobin? Does it have less or greater affinity for oxygen? |
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Definition
a. T (tense) state corresponds to deoxy form, stablilizes increased O2 binding
b. Lower Affinity |
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Term
| 11. How does oxygen binding alter the state (T or R) of hemoglobin? |
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Definition
| a. It changes from T to R thus increasing the O2 affinity |
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Term
[image]20. The partial pressure of oxygen in the venous blood of a human at rest at sea level is 40 torrs (40 mm).
a. What percentage of the oxygen originally bound to hemoglobin in the lungs remains unreleased? (use dissociation curve to read) |
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Definition
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Term
| b. Is the residual oxygen bound to hemoglobin under these conditions of any benefit? Explain |
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Definition
| a. Yes, it is there to ensure if our metabolic rate changes immediately we still have O available to give up to that tissue. |
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Term
| What are allosteric effectors? |
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Definition
| a. Small molecules which bind to the protein at sites that are spatially distinct from the ligand binding site and exert either a positive or negative effect on ligand binding |
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Term
| Does a drop in pH shift the curve to left or right? |
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Definition
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Term
| Does an increase in pH shift the curve to left or right? |
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Definition
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Term
| Where does CO2 bind on hemoglobin? |
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Definition
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Term
| 9. How many CO2’s can bind to hemoglobin? |
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Definition
| 4via covalent attachment, nonenzymatic it can come on and off, binds @ the N terminus |
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Term
| Do carbamate groups stabilize T or R state? |
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Definition
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Term
| 11. Does an increase in CO2 shift the curve to left or right? |
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Definition
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Term
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Definition
| a. Negative heterotropic effector |
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Term
| Does 2,3 BPG shift hemoglobin's curve to left or right? |
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Definition
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