Chapter 10: Proteins, Amino Acids, Enzymes, Peptides Flashcards
What are the 10 essential amino acids
Arginine
Histidine
Isoleucine
Leucine
Lysine
Methionine
Phenylalanine
Threonine
Tryptophan
Valine
What are the 10 non essential amino acids
Alanine
Asparagine
Aspartate
Cysteine
Glutamate
Glutamine
Glycine
Proline
Serine
Tyrosine
What are essential amino acids?
Essential amino acids cannot be made by the body. (must get from food)
What are non essential amino acids
our bodies can produce the amino acid, even if we do not get it from the food we eat.
what is an amino acid structure?
central carbon atom with -COOH,-H2N, and a R group
So
H
|
H2N—C—COOH
|
R group
What is the acid base nature of amino acids
Amino acids can function as both Bronsted-Lowry acids and bases because they have both acidic and basic functional groups
What is a Bronsted-Lowry acid?
any species that can donate a proton
What is a Bronsted-Lowry base?
Anything that can accept a proton
What is the isoelectric point?
is the pH at which a molecule has a net charge of zero
How do you find the net charge?
Subtract protons and electrons
How do you know the atomic number?
The number of protons
What is the mass number?
Protons+neutrons
The zwitterion of an amino acid exists at a pH _____ to the isoelectric point
The zwitterion of an amino acid exists at a pH equal to the isoelectric point
Amide bond condensation reaction is when
The −OH from the carboxyl group of one amino acid combines with a hydrogen atom from the amine group of the other amino acid to produce water
what is an example of an Amide bond condensation reaction
when ethanol is heated in the presence of sulfuric acid, diethyl ether and water are formed:
What is the N terminus?
H2N-CH-C
the first part of the protein that exits the ribosome during protein biosynthesis
What is the C terminus
C-OH
the end of an amino acid chain
what are the 4 levels of the 3D structure of proteins
primary, secondary, tertiary, and quaternary structure.
What is the primary structure of proteins
sequence of a chain of amino acids (Looks like a long snake)
What is the secondary structure of proteins
hydrogen bonding of the peptide backbone causes the amino acids to fold into a repeating pattern. (Looks like folded paper)
What is the tertiary structure of proteins
Three dimensional folding pattern of a protein due to side chain interactions (looks like the snake is laying onto of itself)
What is the quaternary structure of proteins
Protein consisting of more Than one amino acid chain (Two snakes laying on top of each other)
what causes a protein to denature
Heat
what causes a protein to renature
when the denaturing influence is removed
What is a receptor? What’s its function?
-a protein molecule to which substances like hormones, drugs, and antigens can bind.
-This allows them to change the activity of a cell
What is transporters? What is its function?
-Transporters (membrane transport/carrier proteins) are specialized membrane-spanning proteins
- Assist in the movement of ions, peptides, small molecules, lipids and macromolecules across a biological membrane.
What is the transportation of oxygen function
-fundamental to aerobic respiration and the survival of organisms through facilitated diffusion
what is the antibody function? How do they work?
-protect you when an unwanted substance enters your body
-Antibodies bind to these unwanted substances in order to eliminate them from your system.
What are enzymes function?
help speed up metabolism, or the chemical reactions in our bodies.
What is the active site of an ezyme
The part of the enzyme where the substrate binds
What is the substrate of an enzyme
a molecule that an enzyme reacts with at the active site
What is the enzyme substrate complex of an enzyme?
an enzyme with its substrate attached at the enzyme’s active site
What is substrate specificityof an enzyme
The preference of an enzyme for one specific substrate (not all enzyme active sites will accept a substrate)
What are The two ES models of enzymes?
-The lock and key model: substrate is the key enzyme is the lock
-The induced fit model: enzyme active site changes as well as the substrate to fit
How does proximity change enzyme reaction rate
Enzyme proximity effect means the increasing of reaction rate by causing a higher probability of collision when reactants are closer together
How does orientation of a substratechange enzyme reaction ?
-the enzyme constrains the substrates into specific reactive conformations,
- increases the probability that reactants will collide in the correct orientation to react
How does substrate concentration change enzyme reaction rate
At low concentration of substrate, there is a steep increase in the rate of reaction with increasing substrate concentration
How does pH change enzyme reaction rate
Changing the pH outside of this range will slow enzyme activity
How does inhibitors change enzyme reaction rate
fewer substrate molecules can bind to the enzymes so the reaction rate is decreased.
What are the 3 types of enzyme inhibitors
-Competitive Inhibition: binds to the active site and prevents the substrate from binding there.
-Non-competitive Inhibition: binds to a different site on the enzyme; it doesn’t block substrate binding, but it causes other changes in the enzyme so that it can no longer catalyze the reaction efficiently.
-Uncompetitive Inhibition: when an inhibitor binds to an allosteric site of a enzyme, but only when the substrate is already bound to the active site.
The structure of glycine
……………………………..H
|
HO2CCH2NH2 (H2N-C-COOH)
|
H
The structure of alanine
………H
|
(NH2-C-COOH)
|
CH3
The structure of serine
COOH
|
H2N-C-H
|
CH2OH
The structure of lysine
COOH
|
H2N-C-H
|
CH2
|
CH2
|
CH2
|
CH2
|
NH2
The structure of aspartic acid
COOH
|
H2N-C-H
|
CH2
|
COOH
