Enzymes
True or false?
Enzymes do not alter the equilibrium of the reaction
True
a reaction with a positive G that proceeds spontaneously
what is an endergonic rection?
this pathway is not involved in fermentation
Bonus: how is ATP made in fermentation?
this process uses the ETC
What is respiration?
Select all the lab tests Enterobacter aerogenes would be positive for:
A. EMB
B. MR
C. VP
D. Tryptone broth
E. Reversion in KIA media
what is ACE
A substrate binds to a regulatory site on an enzyme which then inhibits its function, this is an example of a:
A. competitive inhibitor
B. positive allosteric effector
C. negative allosteric effector
D. A and B
E. A and C
what is C
Bonus: draw a competitive inhibitor vs an non-competitive inhibitor
which of the following is false?
A. PEP has a higher phosphate energy transfer potential than ATP
B. In the ETC, electrons are donated from more negative to more positive
C. Eo' = (Eo' of oxidizing agent) – (Eo' of reducing agent)
D. The greater the difference in redox potential (Eo') between the redox pairs that serves as the electron donor and the acceptor, the greater amount of energy available (Go') in the oxidation-reduction reaction
E. Go' can tell us the speed of the reaction
What is E?
Which of the following is a carbon skeleton produced in the Pentose Phosphate Pathway? Select all that apply:
A. Glucose-6-phosphate
B. Ribose-5-phosphate
C. Acetyl-CoA
D. α-ketoglutarate
E. Erythrose-4-phosphate
What is B and E
bonus: name where the other answer choices come from
Which of the following is not a coupling site for the mitochondrial electron transport chain?
A. Complex I
B. Complex II
C. Complex III
D. Complex IV
E. All of the above are coupling sites
What is B?
bonus: in what order would an electron donated by FADH travel?
this plate tests for the enzyme that hydrolyzes fats into glycerol and fatty acids
what is lipase plate
bonus: how can fatty acids be used for energy?
Which of the following is true?
A. enzymes along with permeases can reach saturation
B. Pacemakers are always the first enzyme in the pathway
C. Coenzymes are covalently attached to the apoenzyme
D. Covalent modifications are reversible
E. isoenzymes include phosphofructokinase and fructose 1,6-bisphosphate
What is A
The substance being oxidized (give all three names)
what is the electron donor / reducing agent / reductant
Which of the following is true? (select all that apply)
A. EMP, ED, and PPP all convert glucose to glyceraldehyde 3-P
B. KDPG is an intermediate unique to the Entner-Doudoroff pathway
C. The Entner-Doudoroff pathway replaces the first half of the EMP pathway and produces: 1 ATP, 1 NADPH, 1 NADH, and 2 pyruvate per glucose
D. The PPP pathway is a major source of reducing power
E. Fructose-6-phosphate is a 12 carbon skeleton made during PPP
What is ABCD?
Bonus: either: list all the 12 carbon skeletons produced in these 3 pathways or list all the net end products made in these 3 pathways
Which of the following is true?
A. the final electron acceptor in anaerobic respiration is something other than oxygen
B. pmf drives ATP synthase
C. Rotenone and malonate inhibits fermentation
D. A and B
E. All of the above
what is D
this organism is positive for MR and indole
what is E. coli
Take a look at the following diagram, which arrow represents the end product regulating its own branch?
what is Q -> E/G or P -> E/F
Identify the oxidizing agent:
A / A- (-0.07) 2e-
B+ / B (0.56) 2e-
What is B+
draw the TCA cycle
bonus: highlight/ discuss important products
this is the ETC branch used by E. coil during log phase and high aeration
What is the bo branch?
which of the following is false?
A. E. coli would show growth on EMB agar but not PEA
B. 2, 3-butandiol fermenters produce and acetoin intermediate that can interact with Barritt’s reagents
C. In the presence of cytochrome c oxidase, reagent is oxidized and turns dark blue to black
D. B and C
E. All of the above are true
what is E
Which of the following enzymes is paired incorrectly?
A. Ribozymes - RNA in nature and catalyzes peptide bond formation
B. nitrate dehydrogenase - reduces nitrate to nitrite
C. pyruvate dehydrogenase - oxidizes and cleaves pyruvate into acetyl-CoA
D. fructose 1,6-bisphosphatase - found in both glycolysis and gluconeogenesis
E. All of the above are correct
what is E
given the following redox pairs, calculate G in kcal:
A / A- (-0.13) 1e-
B+ / B (0.32) 1e-
what is -10.35 kcal?
Draw the path 1 glucose will take from glycolysis -> TCA -> ETC -> final electron acceptor in anaerobic respiration
(you do not have to write out every intermediate, only the 12 carbon skeletons)
Bonus: draw/ highlight/ point out all products (i.e. ATP, NADH, etc)
This is what happens when Paracoccus denitrificans grows as an autotroph
e- donated to cyt c via methanol dehydrogenase
this nitrate broth result would likely occur when Paracoccus denitrificans is in anoxic conditions
clear tube/ no reaction on day 1 and day 2
bonus: what would inhibit denitrification for Paracoccus?