Metabolism - II Flashcards
catabolism vs anabolism
catabolism - break down macromolecules (hydrolysis) , releasing ATP via oxidation
anabolism - synthesizes complex monomers (reduction) using ATP
*monomers are joined together via dehydration synthesis
most non-photosynthetic organisms are chemoorganoheterotrophs… why?
gives the most ATP per molecule
two major paths of chemoorganoheterotrophic metabolism
- respiration
= ETC to produce ATP via oxidative phosphorylation (glucose fully oxidized to CO2) - fermentation
= produces ATP only from substrate level phosphorylation (glucose partially oxidized to pyruvate)
substrate level phosphorylation vs oxidative phosphorylation
substrate - occurs in glycolysis and Krebs cycle
phosphate - ADP
*no ETC, no proton motive force (PMF)
oxidative - occurs via ETC and a proton gradient, inorganic phosphate is added to ADP
which generates more ATP respiration or fermentation?
respiration
3 stages of aerobic respiration…. how much ATP is generated per one glucose
- 32 ATP
- glycolysis (1glucose - 2pyruvate)
- EMP pathway
- EDP pathway
- PPP pathway - oxidation of pyruvic acid to acetyl CoA
- oxidation of acetyl group to CO2
- Krebs cycle (citric acid cycle)
describe EMP pathway
Embden-Meyerhof pathway
- 2 phases, investment (1 glucose to 2 G3P) & return phase (2 G3P to 2 pyruvates)
input
- 1 glucose
- 2 ATP
output
- 2 pyruvate
- 2 NADH
- 2 net ATP (4 gross)
EDP pathway
(entner doudouroff pathway)
~ gram negative bacteria
- only 1 G3P used to make ATP
- produces 1 pyruvate, 1 ATP, 1 NADH and 1 NADPH
PPP pathway
(pentose phosphate pathway)
allows to catabolize 4/5 carbon sugars
- major source of NADPH
for every 3 G6P: - 1 G3P to make 2 ATP
describe TCA (Krebs) cycle
- cycles twice per 1 glucose/ 2 pyruvates/ 2 acetyl CoA
produces 3 NADH, 1 FADH, 1 ATP, 2
CO2 PER ONE CYCLE
*so double for a full net production
glycolysis and TCA cycle only produced ____ via ______ phosphorylation
4 ATP via substrate level phosphorylation
ETC generates ____ which is used to generate ATP
ETC - PMF (proton motive force) used to generate ATP
which part of oxidative phosphorylation actually generates the ATP
chemiosmosis (using proton gradient generated from ETC)
- protons flow back into cytosol through ATP synthase
ETC pumps H into the ____ and what is the final electron accepter
periplasmic space
final e accepter - O2 ~ forms H2O
what else can PMF be used for (2)
- locomotion (flagella)
- active transport
anaerobic respiration uses a ____ oxygen electron accepter
non oxygen
- uses nitrate!! converted to nitrogen gas in end
NO3- to NO2- to N2
longer ETC = more ___
more ATP, protons
describe fermentation purpose
replenishes NAD+ for glycolysis
rank aerobic, anaerobic, fermentation in terms of most/ least ATP generated
most - aerobic
anaerobic
least - fermentation
1 edible and non edible byproducts of fermentation
edible - cheese, yogurt etc
non edible - rubbing alcohol
oil eating microbes are an example of _____
syntropy, many species work together to clean up oil
describe catabolism of proteins and lipids
proteins - broker into AAs, NH3 molecule removed and then enter glycolysis or TCA cycle
lipids - broken into FAs and glycerol, glycerol enter glycolysis as G3P and FAs turn into Acetyl CoA
