Lecture 6 Flashcards
catabolism
breaking down of “food” for energy and building blocks
anabolism
building of cell components from building blocks and energy
What do you need to consider if you want to grow a culture of microbes?
- nutrients
- temp.
- atmosphere
- pH
- others..?
energy classes
- chemorganotrophs
- chemolithotrophs
- phototrophs
- heterotrophs
- autotrophs
Describe source of “building blocks” for heterotrophs and autotrophs
- uses organic matter as food
- uses inorganic matter
free energy of formation
the energy released or required during formation of a given molecule from the elements
How do cells conserve energy?
by coupling energy released from catabolic rxns
Redox reactions usually involve…
reactions between intermediates
Electron carriers are divided into which two classes?
- prosthetic groups (attached to enzymes)
- coenzymes
NAD+ and NADH facilitate redox reactions without…
being consumed; they are recycled
Which two reaction series are linked to energy conservation in chemoorganotrophs?
fermentation and respiration
fermentation
substrate-level phosphorylation; ATP is directly synthesized from an energy-rich intermediate
respiration
oxidative phosphorylation; ATP is produced from proton motive force formed by transport of electrons
Fermented substance is both an ______________ and an ______________.
electron donor, electron acceptor
Embden-Meyerhof pathway
glycolysis; a three stage, anaerobic and common pathway for catabolism of glucose
Fermentation net yield of ATP
2 for each glucose fermented to lactate
During fermentation, reducing power is generated during…
creation of 1,3-BPG and is consumed to create lactate from pyruvate
During respiration, reducing power is transferred to…
a “terminal electron acceptor”
electron transport
movement of reducing power
aerobic respiration
oxidation using O2 as the terminal electron acceptor
NADH dehydrogenase
proteins bound to inside surface of cytoplasmic membrane that bind NADH and accepts 2 e- and 2 protons that are passed to flavoproteins
flavoproteins
contains flavin prosthetic group that accepts 2 e- and 2 protons, but donates only e- to next protein in chain
cytochromes
proteins that contain heme prosthetic groups and accept and donate a single e- via the iron atom in heme
iron-sulfur proteins
-contains clusters of iron and sulphur that carry e-; reduction potential cary depending on # and position of FE and S atoms
Quinones
- hydrophobic non-protein-containing molecules that participate in electron transport
- accept e- and protons, but pass along e- only
