Biochemistry: Proteins, Rxn Rates, Glycolysis Flashcards
What is the role of the rER?
Pump out generalized proteins
What is the role of the Golgi?
Make proteins specialized
What organelle produces steroids in the adrenal cortex?
Smooth ER
T/F: The mitochondria have a double membrane bilayer.
True
Which organelle contains its own cyclic DNA passed down from mothers?
Mitochondria
What enzyme is often involved in the production of cAMP?
Adenylyl cyclase
Alpha2, Beta1, and Beta2 receptors all work by modifying what enzyme?
Adenylyl cyclase
Amino acids are bound by what type of bonds?
Covalent bonds (strongest)
T/F: Electrostatic interactions are examples of covalent bonds.
False
Electrostatic, hydrogen, and van der waals are all noncovalent bonds
The amino acids in proteins are linked covalently by _________.
peptide bonds (amine bonds)
Aspartate can be broken down into ________.
oxaloacetate
*think ketone bodies
What is the precursor to tyrosine?
Phenylalanine
Melanin, dopamine, epinephrine, and norepinephrine can all be made through ________.
tyrosine
T/F: Lipids, carbohydrates and proteins all contain nitrogen.
False
Just proteins
T/F: Which amino acid is the precursor to serotonin?
Tryptophan
Decarboxylation of histidine leads to which vasodilator?
Histamine
T/F: Histamine is a vasodilator.
True
Dilate vessels, constrict lungs
Which amino acid is a precursor for GABA?
Glutamate
What is the basic protein structure?
Alpha carbon surrounded by four groups:
- Hydrogen
- Carboxyl
- Amino (Nitrogen)
- R group
T/F: All amino acids are in the L-configuration.
True
Which disease is linked to the incomplete metabolism of tyrosine?
Albinism
Deficiency in tyrosinase does not make enough melanin
T/F: The secondary structure of proteins is mediated by covalent bonds.
False
Alpha helicies, beta sheets, random coils
T/F: Tertiary structure is the three dimensional shape of the protein.
True
Globular and fibrous
Albumin is an example of which type of tertiary structure?
Globular (water soluble)
Collagen is an example of which type of tertiary structure?
Fibrous (not water soluble)
Which two amino acids will be found in the globular shape of a protein?
Leucine and valine
X-ray diffraction is the best way to analyze which level of protein structure?
Tertiary
Antibodies are made from what?
Plasma cells (mature B lymphocytes)
Which four amino acids have pyruvate as a precursor?
Al and Lucy Isolate Vallerie
Alanine, Leucine, Isoluecine Valine
Oxaloacetate is a precursor to aspartate which can further produce which amino acids?
All Lice Thrive on Meth
Asparagine, Lysine, Threonine, Methionine
Which amino acid is a precursor for Heme?
Glycine
Serine -> glycine -> heme
Which amino acid is a precursor for nitric oxide?
Arginine
Glutamate -> arginine -> NO
What is the predominant antibody in a primary exposure?
IgM
M is Made first
What is the most plentiful antibody?
IgG
Which antibody is most prominent in the gingiva?
IgG
Which antibody can cross the placenta?
IgG
Which antibody causes bacterial aggregation?
IgA
Which antibody is found in secretions (mucous, tears, saliva, breast milk)?
IgA
IgA inhibits pathogens from _________.
adhering to surfaces
Which antibody binds to allergens triggering a histamine release?
IgE
Type 1 hypersensitivity
Histamine is always found within which two cells?
Mast cells and basophils
What types of symptoms would be seen upon first exposure with a type 1 hypersensitivity reaction?
No symptoms -> IgE would be made and bind to basophils to be ready if exposed again
What leads to histamine release in Type 1 hypersensitivity reaction?
Antigen binds to IgE on surface of basophil -> Ca+ allowed into cell -> depolarization leads to histamine release
What is the basic structure of collagen?
Three polypeptide alpha chains form Triple Helix
What three compounds can hydroxylate proline and lysine?
Vitamin C, ferrous ions, and alpha-ketogluterate
Where does hydroxylation of proline and lysine take place?
Rough ER
Weakened connective tissue, poor wound healing, and bleeding of the gums are all symptoms of which disease?
Scurvy
Vitamin C deficiency
________ is the longest known protein.
Tropocollagen
Which collagen disease will cause a malar rash?
Lupus
Young females, attacks DNA, Malar rash
What allows for elastin to be more flexible than other collagens?
No hydroxylysine and typically no hydroxyproline
What do osteogenesis imperfecta and Ehler’s Danlos syndrome have in common?
Both effect type 1 collagen
Which molecule concentration provides the best estimate of collagen present in a given tissue?
Hydroxyproline
T/F: Carbon monoxide binds to heme groups irreversibly.
True
What is significant about the iron in a heme group?
Must be in a ferrous/reduced state
T/F: Most of the carbon dioxide carried through blood is via hemoglobin.
False
Bicarbonate
________ comprise 90% of enamel proteins.
Amelogenins
Which disease results in a thin hypoplastic enamel layer?
Amelogenesis imperfecta
Which vitamin insufficiency will result in a hypoplastic enamel layer?
Vitamin A and Vitamin D
What is Km?
The concentration of substrate needed to reach 1/2 of V max
What will be the effect of competitive inhibition?
It will decrease binding affinity so Km will increase (need more substrate to overcome competition)
T/F: Competitive inhibition causes a shift in which direction?
To the right
What is the effect of non competitive inhibition?
No effect on Km, will decrease Vmax
Graph shifts down
In a Lineweaver-Burke plot, an uninhibited reaction will have the same point on the y axis as a non competitive reaction.
False
1/velocity is represented on the Y axis so competitive and uninhibited will share point on y axis, non competitive will shift up
T/F: Allosteric ligands bind to the active site.
False
Bind away from the active site
______ is an example of an allosteric ligand.
ATP
T/F: ATP can be a substrate and an allosteric inhibitor.
True
What does it mean if a reaction results in a negative change in G?
Energy is given off in the rxn
T/F: Energy is released in an endergonic reaction which would have a negative change in G.
False
Energy released = exergonic = negative change in G
What two thermodynamic parameters would lead to an exergonic reaction (-deltaG)?
Entropy (+deltaS) = lots of randomness
Enthalpy (-deltaH) = heat given off
T/F: Enzymes have no effect on reaction equilibrium.
True
T/F: When a molecule gains electrons it is oxidized.
False
Leo says Gerrr
Lose electrons oxidized
Gain electrons reduced
What is the main role of NADPH?
Electron carrier in the pentose pathway shunt -> reduces molecules
What is the main role of NADH/FADH?
Electron carriers in Krebs cycle etc. Oxidated to form ATP
What is the definition of pH?
pH = -log(H)
H = concentration of protons
T/F: pH + pOH = 14
True
If H+ concentration is 10^-5 what will the pOH be?
pH = 5 pOH = 9
What is the major buffer when H+ ions are released inside the cell?
Dihydrogen phosphate
What is the major buffer when H+ ions are released outside the cell?
Carbonic acid
Why are proteins such good buffers?
They contain many different functional groups with different pKa values
Describe the basis of the Henderson-Hasselbalch equation?
pH = pKa when the acid is half neutralized
pH = pKa + log (base/acid)
Transamination and oxidative deamination are both examples of what process?
Protein metabolism
Which three amino acids are not transaminated?
Lysine, serine, and threonine
__________ is required as a coenzyme for transamination.
Vitamin B6
Transaminases cleave the ________ from amino acids.
alpha amino nitrogen
Which amino acid undergoes rapid oxidative deamination?
Glutamate
What are the two results of oxidative deamination?
alpha ketoacids or amonia
What is the major enzyme that does oxidative deamination?
Glutamate dehydrogenase
What is the major method of metabolism for anaerobic and facultative anaerobic bacteria?
Glycolysis (Embden-Meyerhof pathway)
Does not require oxygen
What is the alternative metabolism method used by some aerobic bacteria?
ENTNER–DOUDOROFF PATHWAY
What byproduct of glycolysis is cariogenic?
Lactic acid
Where does glycolysis occur?
In the cytosol
