Intro To Protein Structure Flashcards
Nonpolar amino acids
Glycine Alanine Proline Valine Leucine Isoleucine
Aromatic amino acids
Phenylalanine
Tyrosine
Tryptophan
Polar uncharged amino acids
Aspiragine
Glutamine
Serine
Threonine
Sulfur-containing amino acids
Methionine
Cysteine
Charged amino acids
Asparate -
Glutamate -
Arginine +
Lysine +
Histidine +
AAs with which chirality type are found predominantly in human proteins?
L-form
D-form AAs are commonly where?
Bacterial cell walls
Cysteine residues make up a large part of what protein?
Keratin (24%)
Explain how an alpha-helix can contain AAs with both polar and nonpolar side chains
The polar side chains can face into the aqueous environment on one side while the nonpolar side chains face into a nonpolar environment on the opposite side
Only ____ residues out of ____ are identical in myoglobin and hemoglobin
15, 146
Factors that may cause denaturation of proteins
Heat, radiation, pH, solvent solution, oxidative damage
What are Heinz bodies?
Protein aggregations resulting from the exposure and aggregation of proteins, making them insoluble
How are Heinz bodies formed?
Oxidative damage–>oxidative O2 species–>Hb denaturation–>protein aggregates–>hemolysis–>anemia
Prion diseases are characterized by the abnormal folding of proteins in what way?
Abnormal beta sheets
T/F Prion diseased proteins maintain the same primary structure as nondiseased proteins
T
Which protein is often the offender in prion diseases?
PrP protein
The consolidation of beta sheet fibers produces what structures?
Amyloid fibers
What type of stain is used to identify prion diseases pathologically?
Congo red (it’s actually yellow)
Molecular chaperones work in which two ways?
- Binding defective proteins to be destroyed with ubiquitin ligase
- Binding oligomers to prevent aggregation
Hb binds each subsequent oxygen molecule with more affinity than the previous. This is known as
Positive cooperative binding
Hb subunits can be in one of two states:
T (tense)
R (relaxed)
This compound promotes salt bridge formation between Hb subunits and decreases oxygen binding to Hb
2,3-BPG (2,3-bisphosphoglyerate)
T/F The glycosylation of Hb is a nonenzymatic, reversible reaction
F
What is the approximate normal HbA1c for nondiabetic adults?
~5%
Glycocylation of what type of cardiac tissue may result in cardiomyopathy?
Collagen
How many base pairs are abnormal in sickle cell disease?
(1) – valine instead of glutamate
Sickling of RBCs causes tissue damage in what progression?
occlusion–>hypoxia–>necrosis
Name a common prion disease
Creutzfeldt-Jakob disease
