Microbial Metabolism (Catabolism - #3) Flashcards
2 phases of glycolysis:
1) energy investment phase
2) energy payoff phase
how many ATP are used in the energy investment phase of glycolysis?
2 ATP
how many ATP are FORMED during the energy payoff phase in glycolysis?
4 ATP
net products of glycolysis (4):
- 2 pyruvate
- 2 H20 (water)
- 2 ATP
- 2 NADH + 2H+
electron carrier in glycolysis =
NAD+
pathway of glycolysis goes from ______ to _______
glucose to pyruvate
Fermentation is an ________ of glycolysis
extension
fermentation does NOT equal _____ _______
anaerobic respiration
fermentation takes place in the absence of an ________ _____ ______
exogenous electron acceptor (O2 not needed)
______ is not needed in fermentation
oxygen
fermentation uses a ________ or ______ as an electron acceptor
pyruvate or derivative
pyruvate or derivative in fermentation is __________
REDUCED
fermentation continues recycling of ______ ______
electron carriers
recycling of electron carriers in fermentation: _________ from glycolysis is OXIDIZED to _______
NADH; NAD+
which pathway does fermentation form ATP through?
substrate-level phosphorylation
fermentation produces various fermentation ______
products
what 2 things does fermentation NOT involve the use of?
- ETC
- proton motive force (PMF)
electron acceptor that comes from the outside of the system
exogenous electron acceptor
electron acceptor that was formed within the system
endogenous electron acceptor
Which of the following statements is TRUE?
a) oxidative phosphorylation is used by all bacteria to make ATP
b) strictly fermentative bacteria use substrate-level phosphorylation to make ATP.
c) oxidative phosphorylation uses proton motive force to make ATP.
d) substrate-level phosphorylation involves the use of the ETC
c) oxidative phosphorylation uses proton motive force to make ATP.
fermentation produces are _______ products to the fermenting organism
waste
purpose of waste products in fermentation =
recycle NADH back to NAD+ so it can continue the cycle
after forming pyruvate in glycolysis, which 2 pathways can a cell take?
- form LACTATE
- form another substance (acid aldehyde) and then form ETHANOL
fermentation classes (2):
1) ethanol
2) lactic acid
fermentation class: breads, wine, beer
ethanol
Lactic Acid groups (2):
- homolactic
- heterolactic
lactic acid group: sole product is LACTIC ACID
homolactic
lactic acid group: make lactate + other stuff
heterolactic
lactic acid group: cheeses, sour cream, yogurt
homolactic
lactic acid group: sauerkraut, pickles, buttermilk, and involved in FOOD SPOILAGE
heterolactic
what kind of other products can heterolactic pathways make (4)?
- acetic acid
- propionic acid
- mixed acid
- 2-3-Butanediol
fermentation classes are based on the main ______
products
Fermentation Pathways (3):
- Mixed acid
- Butanediol
- swiss
fermentation pathway: several pathways simultaneously
mixed acid
what reagent detects mixed acid fermentation pathway AND at what pH/
methyl red (MR) @ a pH of 5 and under
fermentation pathway: intermediate called ACETOIN
Butanediol
what test detects Butanediol/acetoin production?
Voges-Proskauer (VP)
butanediol is also known as ______
acetoin
genus of swiss cheese is the same genus that causes _____
acne
T/F: you can have a fermentation test that is positive for both MV and VP
false!
what REAGENTS in VP detect precursors of Butanediol/acetoin?
Barritt’s A and Barritt’s B
in the Butanediol pathway, is acetoin produces or precursors of acetoin?
PRECURSORS
chemoorganotrophic fuelding process involves _____
respiration (both aerobic + anaerobic)
respiration uses _____ ____ and ______, UNLIKE fermentation
oxidative phosphorylation and ETC
2 types of respiration:
1) aerobic respiration
2) anaerobic respiration
type of respiration: final electron acceptor is oxygen
aerobic
type of respiration: final electron acceptor is DIFFERENT exogenous e- acceptor such as NO3, SO4, CO2, Fe3+, or SeO4
anaerobic
ATP is made primarily by what pathway?
oxidative phosphorylation
what 2 things does oxidative phosphorylation involve?
- ETC to generate a proton motive force
- ATPase to make ATP
what generates a PMF in oxid. phosphorylation?
ETC
what makes ATP in oxid. phosphorylation?
ATPase
ATPase is also known as ______
ATP-synthase
ETC can be _____ specific
species (net of 38 ATP varies)
the ETC is the electric ______
tower
the _______ the ETC, the more energy it releases
longer
if the cell has poor nutrition, the cell might make the ETC _____
shorter
in Eukaryotes, the ETC is located where?
inner mitochondrial membrane
in Bacteria and Archaeons, the ETC is located where?
cytoplasmic membrane (dont have mitchondria)
series of electron carriers that operate together
ETC
in the ETC, electrons are transferred from _____ and _____ to a terminal electron acceptor
NADH and FADH2
in ETC, electrons flow from carriers with more ______ E0’ to carriers with more ______ E0’
negative to positive
ETC: as electrons are transferred, energy is released to make ATP by _______ ______
oxidative phosphorylation
does NADH or FADH2 give more energy?
NADH (comes in higher on the tower)
the CHANGE (delta) in E0’ is how many volts?
1.14 V
what does the P and the O stand for in P/O ratios?
proton and O2 (oxygen)
P/O ratios really have to do with ____
protons
P/O ratio: ____ ATP for every NADH
3
P/O ratio: _____ ATP for every FADH2
2
in the ETC, _____ comes in complex 1 because of its standard reductin potential
NADH + H+
in the ETC, _____ comes in complex 2
FADH2
where does the CAC cycles occur in the ETC?
complex 2
how many protons are released in Complex 1?
4
how many protons are released in Complex 3?
4
how many protons are released in Complex 4?
2
free energy released per 2 electrons (delta G0’) =
-220 kJ
the movement of ions across a semipermeable membrane bound structure, down their electrochemical gradient
Chemiosmosis
in Complexes 1, 3, and 4, protons move from the _____ to the ____ ______
matrix to the intermembrane space
in ATP-ase, protons move from where to where?
intermembrane space ot matrix
how many protons go through the ATPase from from the intermembrane space to the matrix?
3
the movement of protons established ______
PMF
ATP synthase uses proton flow ______ the gradient (into the cell) to make ATP
DOWN
smallest biological motor
ATP-ase
ATP-ase is _______, can also break ATP to make PMF
reversible **
what can ATP-ase be used for when it is put in reverse and BREAKS ATP to produce a Proton Motive Force?
spinning flagella
part of ATP-ase: structure in nature
alpha + delta
part of ATP-ase: where magic happens
beta
ATP is released in ATP-ase when Beta goes back to what position?
original (empty)
where is ATP is released from ATP-ase ?
inside the cell (cytoplasm)
part of ATP-ase: headpiece; consists of alpha, beta, sigma, and gamma, INSIDE the cell (cytoplasm)
F1
part of ATP-ase: proton channel made here**; consists of epsilon and “a”; PART of MEMBRANE; where protons go IN from the outside of the cell
F0
parts of ATP-ase: holds up head piece and keeps it stable so it can’t spin; energy is used to make confromation changes to beta
gamma + epsilon
conformation changes in ATP site means….
active site changes
why do bacteria make fermentation products during the process of fermentation?
to oxidize NADH
steps in which electrons travel to make ATP (all reversible - 4)
1) electron donors
2) electron transport
3) proton motive force
4) prod. of ATP
process that can completely catabolize an organic energy source to CO2
aerobic respiration
3 pathways/processes in which aerobic respiration completely catabolizes an organic energy source:
1) glycolytic pathway
2) CAC (Kreb’s cycle)
3) ETC with oxygen as final e’ acceptor
glycolytic pathway ends at ____
pyruvate
CAC (kreb’s cycle) is also called the _____
TCA (tricarboxylic acid cycle)
which process in aerobic respiration gives you the most ATP production?
ETC w/ oxygen as final e- acceptor
aerobic respiration produces ATP mostly by what process?
oxidative phosphorylation
aerobic respiration produces ATP and recycles ______ _____
electron carriers
e- dump in aerobic respiration =
ETC (thru NADH to NAD+ or FADH2 to FADH)
there are ____ stages of aerobic catabolism
3
stage of aerobic catabolism: proteins, polysaccharides, and lipids are broken down into their monomers
stage 1
stage of aerobic catabolism: monomers are broken down into either NH3 (from protein), pyruvate (from monosaccharides), or acetly-Coa (from lipids)
stage 2
stage of aerobic catabolism: CAC (kreb’s cycle) occurs
stage 3
in which stage of aerobic catabolism is the FIRST ATP released?
stage 2
how is the first ATP released in stage 2 made?
substrate-level phosphorylation (during glycolysis)
you don’t get any NET ATP until the ______
ETC
T/F: glucose is not always completely taken down to CO2 and
true
after the CAC (kreb’s cycle), ATP is made by what process?
oxid. phosphorylation
INDUCIBLE enzymes in aerobic catabolism; can be turned ON/OFF; depends on what they detect in their environment
Exoenzymes
examples of an exoezyme made when starch in in the environment
amylase
CONSTITUTIVE enzymes in aerobic catabolism; always ON; need them regardless of what type of food is in the environment
Endoenzymes
in stage 1 of aerobic catabolism, the cell digests polymers ______ of the cell to make it small enough for the use of enzymes
outside
which stage do EXOenzymes break down molecules?
stage 1
which stage do ENDOenzymes break down molecules?
stage 2
exoenzymes are ______
inducible (turn on/off)
endoenxymes are ______
constitutive (always ON)
stage 2 and 3 includes ______ pathways – enzymes are reversible and can be used for anabolism (build up)
amphibolic
T/F: protiens, polysaccharides (starch), and lipids are come into the same pathway in aerobic catabolism
true
polysaccharides =
starch
if a food source is not there (such as lipids), the specific exoenzyme is ____
off
in glycolysis, how many ATP are made via SLP
2
in glycolysis, how many NADH** are made via oxididative phosphorylation?
6
in glycolysis, how many NADH are reduced to get 6 ATP?
2
(P/O of x3 for NADH to get 6 ATP)
in the bridge step, _____ is converted to _____ after glycolysis
pyruvate to Acetyl Co-A
in the bridge step, _____ NADH are reduced to get ______ ATP
2 NADH; 6 ATP
in glycolysis, _____ NADH are reduced to get ____ ATP
2 NADH; 6 ATP
in CAC, _____ NADH are reduced to get _____ ATP via oxid. phos.
6 NADH; 18 ATP
in CAC, ______ FADH2 are reduced to get _____ ATP via oxid. phos.
2 FADH2; 4 ATP
in CAC, _____ ATP are made via SLP
2
in CAC, how many total ATP are made via OXID. PHOSPHORLYATION?
22
how many total ATP are made via SLP in aerobic respiration?
4
how many total ATP are made via oxid. phos. in aerobic respiration?
34
how many total ATP are made in aerobic respiration?
38
the CAC goes through the cycle _____ to get its 24 total ATP?
twice
anaerobic respiration uses electron carriers other than _____
oxygen
electron carriers in ANAEROBIC respiration are lower on the tower so they release _____ energy
less
in anaerobic respiration, the E0’ of final electron acceptor is less ______ than E0’ of oxygen
positive
