lect 7/8: microbial metabolism Flashcards
(28 cards)
define heterotrophs
use organic molecules as carbon sources which often also serve as energy sources
define autotrophs
use CO2 as their sole/principal carbon source and must obtain energy from other sources
define lithotrophs
use reduced inorganic substances
what does glycolysis produce
At and reduces NAD+ to NADH while oxidizing glucose to pyretic acid
what does the krebs cycle do
produces some ATP by substrate phosphorylation, reduces NAD+ and FAD, and gives off CO2
what is the final electron acceptor in aerobic respiration
Oxygen
what is the final electron acceptor in anaerobic respiration
different exogenous acceptor (besides oxygen)
how is ATP synthesized for fermentation
substrate-level phosphorylation
where does the embden-meyerhof pathway occur
cytoplasmic matrix
what are the 2 phases of EM pathway
six carbon phase and 3 carbon phase
what does the oxidation step of the EM pathway produce
NADH
what is the net outcome of the EM pathway
2 pyruvate, 2ATP, 2NADH and 2H+
what uses the entner-duodoroff pathway
soil bacteria and a few gram negative bacteria
what is the yield per glucose in the ED pathway
1 ATP, 1 NADPH, and 1 NADH
what is the main product in the pentose phosphate pathway
NADPH
what is the net outcome for the PPP
6CO2, 12 NADPH, and 12H+Pi
what is the major role of the TCA cycle
source of carbon skeletons for use in biosynthesis
what does each acetyl CoA molecule generate
2 molecules CO2, 3 molecules NADH, one FADH2, and one GTP
how many ATP molecules are synthesized directly from oxidation of glucose to CO2
4 ATP molecules
where does ETC occur in bacteria and archae
plasma membrane
what is the upper branch of the ETC in bacteria
stationary phase and low aeration
what is the lower branch of the ETC in bacteria
log phase and high aeration
what does ATP synthase use to catalyze ATP synthesis
PMF down gradient
define dissimilatory nitrate reduction
use of nitrate as terminal electron acceptor, making it unavailable to cell for assimilation or uptake
