Unit 2, 3, & 5 (Amino acids, Proteins, Hemoglobin) Flashcards
an alpha carbon is…
the central carbon atom of every amino acid
an amino acid consists of…
an amine group, carboxyl group, and an R group with a central (alpha) carbon atom
how many different amino acid groups are there?
20
the amino group, carboxyl group, and central carbon make up…
the amino acid backbone
the amine group of an amino acid consists of…
hydrogen and nitrogen atoms (NH3+)
the carboxyl group of an amino acid consists of…
one carbon and 2 oxygen atoms (COO-); has lost its hydrogen
Nonpolar (hydrophobic) amino acids all have what type of “R” group build?
Will a nonpolar amino acid interact/bond with a polar amino acid?
What type of interaction?
carbons (C) bonded to hydrogens (H) atoms (weak bonds).
No, nonpolar amino acids will only interact/bond with other nonpolars.
Hydrophobic interactions.
Nonpolar (hydrophobic) amino acids are disrupted by…
heat
Polar, uncharged amino acids contain…and form this type of bond____, unless 2 cystine (sulphur) amino acids bond, then the bond is a…
sulphur (S), oxygen (O) or nitrogen (N) bonded to hydrogen (H).
hydrogen bond (strong); biochem is a SON of a
disulfide bond.
Polar amino acids (except cystine) hydrogen bonds are disrupted by…
Cystine disulfide bond is broken by…
pH and salt changes.
a reducing agent.
The amino acid _____ can produce a _____ bond, the strongest, and requires a ______ agent to disrupt the interaction.
cystine; disulfide; reducing
Charged amino acids will consist of ___, ___, or ___ bonded to hydrogen (H) and form ____ bonds disrupted by…
sulphur (S), oxygen (O), or nitrogen (N)
ionic
pH and salt changes.
Peptide bonds hold together amino acids at what level of protein structure?
Primary
Tertiary protein structure is noted when ___ ___ and ___ ___ attractions cause ___ folding and a ___D shape.
a-helix, b-pleated sheets
distant
3
The 4 R-group interactions are…
Hydrophobic interactions (nonpolar)
Hydrogen bonds (polar)
DIsulfide bonds
Ionic bonds (charged)
The 4 R-group interactions can stabilize what levels of protein folding?
Tertiary and Quaternary
A protein structure consisting of more than one amino acid chain with subunits…
Quaternary protein structure
Hg and antibodies are made up of ____ protein structure, and the body can replace a ____ instead of the entire structure if needed.
quaternary
subunit
_____ inhibitors attach somewhere other than the active site, alter the shape/confirmation of the enzyme and active site, making the active site nonfunctional.
Another name for these inhibitors is ____
Noncompetitive
Allosteric (allo = other)
Competitive inhibitors ____ with substrates mimicking their behavior and attach at the ____ ____ of an enzyme.
compete
active site
What is the substrate of aldolase B, and how do you know that?
F1P
Substrate is always before the arrow of the reaction.
Identify the enzymes.
How do you know that?
Fructokinase and Aldolase B
They end in ase, and in pathway examples, they are above the arrows.
Can F1P be a product?
Yes, it’s the product of fructokinase.
Substrates can be products as well as substrates.
What would happen if aldolase B didn’t function?
DHAP and Glyceraldehyde would not be produced, but F1P would accumulate.
How could we increase the amount of DHAP and glyceraldehyde produced?
Increase the amount of F1P, but to do that, you have to increase the intake of fructose.
Identify the products in this pathway.
Identify the substrates/reactants.
What does the blunt line in this pathway represent?
The F molecule is causing inhibition to the enzyme in step 2. Also called feedback inhibition, d/t a product of the pathway inhibiting a step in the same pathway.
C is the substrate for E4, which helps convert C to X. If you inhibit E1, C is unable to be produced, therefore X is decreased or not made.
E3 catalyzes substrate D to F, and F inhibits E4. When E3 is inhibited, product F can’t be made. If F isn’t made, E4 is no longer inhibited, so E4 will then increase the production of X.
What is an Allosteric site?
It is the binding site on Allosteric enzymes - enzymes that have an additional site for an effector to bind to, as well as the active site.
Kinase
An enzyme that catalyzes the transfer of phosphate groups - a substrate phosphate donating molecule) to the product, which is a phosphate acceptor. These are known as phosphorylation types of reactions.
Phosphatase
An enzyme that catalyzes the opposite of the kinase types of reactions. Phosphatase removes a phosphate group from the substrate. These reactions are known as the dephosphorylation types of reactions.
Define affinity
Which has higher affinity for O2, Hemoglobin or Myoglobin?
How “sticky” the protein is to oxygen.
Myoglobin - bc it stores O2
The higher the curve, the higher the affinity of that protein.
What is the function of hemoglobin?
How many subunits does it have?
How many heme groups, iron, and O2 molecules does it carry?
Pick up O2 in the lungs and deliver it to hypoxic tissues.
4
Each subunit binds to 1 heme group = 4
Each heme group associates with 1 iron (Fe) = 4
Each iron binds to 1 O2 molecule = It can carry and transport 4 O2 molecules
What is myoglobins function?
How many subunits?
How many heme groups, iron, and O2 molecules does it store?
Store O2 in the muscles.
1
1 subunit binds to 1 heme group
The 1 heme group associates with 1 iron
The 1 iron binds to the 1 O2 molecule it can store.
How do changes in pH affect the ability of hemoglobin to bind (affinity) or release O2?
Higher pH (Left shift) = higher affinity to O2, will bind to O2 more readily in lungs, low H+
Lower pH (Right shift) = lower affinity to O2, will release O2 easily in muscles d/t high H+ and low O2
