Flashcards in Metabolism and Energetics Deck (47)
Microbes must be able to use available ___ from their environment to make all ___/___ required for ___, ___, and ___
What is anabolism?
production of macromolecules/chemicals from building blocks and ATP
What is the reducing power for anabolism provided by?
What is catabolism?
generation of energy (ATP) and reducing power (NADH+H) from nutrients, byproducts may be used for anabolism
culture medium is ___ to the microbe
What are enzymes?
biological catalysts that lower the activation energy needed for reaction
What is delta G?
What do negative and positive values of delta G represent?
negative: release of energy
positive: absorption of energy
What is activation energy?
the energy required to put all molecules into reactive state
What is a catalyst?
a substance that lowers activation energy without changing the free energy, only changing the rate
REDOX reactions exist in pairs because e- cannot exist in ___, ___ of one substance is linked to the ___ of another
Oxidation is ___ of e-, reduction is ___ of e-
The e- donor is the ___ source
___ provide the reducing power for the reactions
Energy-rich compounds are rich because they have high energy ___ that, when broken, release lots of energy
What are the three basic metabolic pathways?
glycolytic, pentose phosphate, and tricarboxylic acid pathways
What are the two series of reactions?
fermentation and respiration
Briefly describe fermentation
organic compounds are e- donors and acceptors, ATP is produced by substrate level phosphorylation
Briefly describe respiration
organic compounds are oxidized to CO2 with O2 or a substitute as the final e- acceptor, most ATP is produced by oxidative phosphorylation
What is the net yield of glycolysis?
- 1 glucose --> 2 pyruvate
- 2ATP (substrate level)
What is the net yield of the citric acid cycle per cycle?
- pyruvate --> acetyl-CoA
- 2 CO2
- 1GTP--> 1ATP
Where does pyruvate oxidation take place?
the pyruvate dehydrogenase complex
What is the succinate dehydrogenase?
large PRO complex located in the membrane, linked to the citric acid cycle
What is the result of full oxidation of acetyl-CoA?
___ must be regenerated or TCA cycle stops
What is oxidative phosphorylation?
process that uses energy produced by respiration to synthesize ATP
What is the difference between aerobic and anaerobic respiration?
aerobic has O2 as the final e- acceptor
What is the respiration chain?
a series of e- and H+ carriers that undergo redox reactions
(ETC) When a reduced substance is oxidized (___) the ___ are transferred to a ___ carrier (FMN), the ___ are then transferred to the next carrier in the sequence
(ETC) is the next carrier is an e- carrier the e- will be ___ and the protons will be ___, if the carrier after is a proton carrier ___ protons must be ___
accepted/released to the outer phase/2/taken in
In the final steps of the ETC, ___ and ___ from the ___ phase reduce O2-->H2O
What are the official names and carriers for:
complex I, Q, complex II, complex III, cyt c, and complex IV
complex 1: NADH dehydrogenase, FMN (H+ carrier) and Fe-S (e- carrier)
Q: quinione (H+ carrier)
complex II: succinate dehydrogenase, FAD (H+ carrier)
complex III: cytochrome bc, Fe-S (e- carrier)
cyt c: cytochrome C (e- carrier)
complex IV: (e- carrier)
What is the proton motive force?
the result of respiration generates a transmembrane proton gradient which is a potential source of energy used to drive other energy requiring reactions
What is oxidative phosphorylation?
synthesis of ATP using the PMF
What is the proton motive force equation?
(pff) = (membrane potential) - [(z conversion factor)(transmembrane gradient)]
What is the net yield of energy from respiration?
When does fermentation happen?
When the terminal e- acceptor isn't available (O2) succinate cannot be oxidized by succinate dehydrogenase in the ETC
Glycolysis can happen as long as ___ can be oxidized back to ___
In fermentation ___ is the e- donor and ___ is the final electron acceptor
an organic compound/an organic degradation product
What is the pentose phosphate pathway?
an alternative to glycolysis, NADPH is used as the reducing power to convert glucose to other sugars, this contributes to a diversity of sugars in the cytoplasm
In the pentose phosphate pathway, ___ may be used to produce ribose then ___
What are the net products of the pentose phosphate pathway?
- a sugar
What are some other roles of the citric acid cycle?
- alpha-ketoglutarate becomes the glutamate family
- oxaloacetate becomes the aspartate family
What are anapleurotic pathways?
pathways that feed the citric acid cycle intermediates
What are some locations of catabolism in eukaryotes?
TCA cycle, respiration, and oxidative phosphorylation in the mitochondria and glycolysis and fermentation are in the cytoplasm
What are some locations of catabolism in prokaryotes?
respiratory chain in the cytoplasmic membrane, glycolysis, TCA cycle, and fermentation in the cytoplasm