Oucom- De Angelis Lectures

Front 1

What are the 4 levels of protein structure

Back 1

primary, secondary , tertiary, and quaternerary

Front 2

What level includes a-helix and B-sheet formations?

Back 2

Secondary

Front 3

What does a basic chiral L-aa look like

Back 3

+ amino to the left, COO- to the right, H on top and R on bottom

Front 4

What is the name of the stage/form where an aa's charge is "neutral" ?

Back 4

zwitterionic

Front 5

T/F - at LOW pH, less protons are present in solution

Back 5

FALSE

Front 6

Name the 4 types of weak bonds/ forces?

Back 6

ionic bond, hydrogen bond, hydrophobic, and van der Waals forces

Front 7

Where are peptide bonds formed?

Back 7

ribosomes

Front 8

Where is the only source of rotation in a peptide bond?

Back 8

around the a-carbon

Front 9

Why is there only rotation around the a-carbon?

Back 9

steric hinderance, and the trans configuration only allows certain angles to form; additionally, electrons are delocalized to form partial double bonds

Front 10

What is the most abundant protein in the human body?

Back 10

collagen

Front 11

Where does the site of glycosylation occur in collagen?

Back 11

hydroxylsine

Front 12

In collagen, what enzyme intiates cross-linking of lysines?

Back 12

Lysyl oxidase

Front 13

In lysyl oxidase, what co-factor is necessary for its function?

Back 13

Copper

Front 14

Which os the following can denature or kill proteins? A) heating B) pH changes C) Solvent changes D) Toxic ligands E) All of the Above

Back 14

All of the above

Front 15

What type of linkages often help hold shade in tertiary structures?

Back 15

disulfide linkages

Front 16

What enzyme is needed to form hydroxyproline?

Back 16

Prolyl hydroxylase

Front 17

In this same enzyme, what co-factor is needed to function?

Back 17

Iron ascorbic - Vitamin C

Front 18

In scurvy, what vitamin is deficient?

Back 18

Vitamin C

Front 19

What does Vitamin C form (specific aa)?

Back 19

Hydroxyproline

Front 20

What aa is involved n disulfide cross-linking?

Back 20

Cysteine

Front 21

What type of proteins are used to "optimize performance" for function in other tissues or developmental stages?

Back 21

Isoforms/ Isozymes

Front 22

In osteogenesis imperfecta, a pont mutation impairs what type of formation?

Back 22

triple helix formation

Front 23

is osteogenesis imperfecta worse when the mutation occurs at the C or N -terminus?

Back 23

C - terminus (because the helix starts zipping up from the C terminus)

Front 24

What is the typical cause of Ehlers-Danlos syndrome (stretchy skin, loose joints, etc)?

Back 24

no cross-linking (no strength) or failure to remove N-peptide (collagen not soluble)

Front 25

Which mutation leads to a severe to lethal disease in collagen? (nonsense or missense mutation)

Back 25

missense mutation - doesn't fold correctly but still incorporates into collagen fibers and thus 3/4 of fibers are bad

Front 26

Emphysema invovles what fibrous protein?

Back 26

elastin

Front 27

T/F In osteogenesis imperfecta, if glycines are mutated closer to the N-terminus, more severe symptoms will be observed?

Back 27

FALSE

Front 28

What is the name of the molecule when water gets into the hydrophobic pocket of hemoglobin and gets to the heme?

Back 28

met-hemoglobin (MHb)

Front 29

The oxygen dissociation curve for hemoglobin and myglobin are _____ and ____ shape?

Back 29

hemoglobin - sigmoidal myglobin - hyperbolic

Front 30

When decreasing the pH oxygen is released more readily, what is this effect called?

Back 30

Bohr Effect

Front 31

What is the Bohr Effect?

Back 31

The shifting of the oxygen dissociation curve right with decreasing pH

Front 32

CO2 covalently binds to N-terminus of Hb chains and forms ___ which has a _____ O2 affinity.

Back 32

Carbonyl Hb and LOWER O2 affinity

Front 33

The following has a POSITIVE effect or NEGATIVE effect on Hb? O2 concen - CO2 Concen - BPG - pH

Back 33

O2 - concen +; Co2 - -; BPG - -; pH - -

Front 34

As [BPG] increases under hypoxic conditions, O2 unloading is (enhanced or decreased) in tissues?

Back 34

enhanced

Front 35

Does BPG bind to fHb more or less tightly?

Back 35

less tightly

Front 36

Why does BPG bind less tightly to fHb?

Back 36

Ser residue substituted for His in fHb; Ser makes overall Hb molecule LESS positive therefore BPG (-) bind less

Front 37

Elastin must be removed during frowth and repair, but cannot remove so much that the integrity of the tissue is compromised. Thus, there is a balance between ___ and ___.

Back 37

elastase and a-antitypsin

Front 38

Name the missing structures in the chain of a-keratin formation? A-helix - __-microfibril-___

Back 38

protofibril and macrofibril

Front 39

What are the modes of catalysis for enzymes?

Back 39

division, concentration, orientation, and strain

Front 40

Acute pancreatitis is caused by what?

Back 40

premature activation of zymogens

Front 41

T/F Enzymes increase reaction rates by changing the equilibrium constants of reactions.

Back 41

FALSE

Front 42

Enzymes are which of the following types of cofactors? A) coenzymes B) prosthetic groups C) metal ions D)all of the above

Back 42

All of the above

Front 43

What type of reversible inhibition works best when: a) [S] is high? B) [S] is low?

Back 43

a) uncompetitive inhibition b) competitive inhibition

Front 44

In competitive inhibition, Vmax is ____ and Km is _____.

Back 44

Vmax - unchanged and Km - shifts to higher value

Front 45

In noncompetitive inhibition, Vmax is ___ and Km is ___.

Back 45

Vmax - lowered and Km - unchanged

Front 46

Sickle cell anemia patients are instructed to avoid hypoxea and dehydration because it will (increase or decrease) deoxy HbS concentration. What are two treatment option for these patients?

Back 46

A) Increase B) cyanate (inc. O2 affinity) and hydroxyurea (turns on fetal Hb synthesis)

Front 47

Why don't allosteric enzymes obey typical kinetics?

Back 47

allosteric enzymes are sigmoidal on MM plots (typical enzymes are hyperbolic)

Front 48

T/F Activities of enymes can range from immediate reactions to reactions that last days.

Back 48

TRUE

Front 49

What is thrombosthenin

Back 49

smooth muscle protein in platelets that tightens clot

Front 50

Problems with cloting will occur for patients who have low Vitamin ___ levels

Back 50

K

Front 51

Where do platelets bind during the blood coagulation process? Via recognition of what "factor" protein?

Back 51

Subendothelial cells via von Willebrand factor protein

Front 52

Which is formed first in the coagulation process Thrombin or Fibrin?

Back 52

Thrombin - activates reformation of fibrinogen into fibrin

Front 53

What is the name of the enzyme that cleaves fibrin triple chain rods?

Back 53

plasmin protease

Front 54

T/F Prostaglandin I2 (PGI2) from activated platelets stimulates healthy intact endothelial cells to produce thromboxane (TxA2).

Back 54

FALSE - thromboxane stimulates production of PGI2

Front 55

What inhibits thrombin when it strays too far from the clot site (2x)?

Back 55

Heparin and Antithrombin III