Bioenergetics Overview Flashcards
How much energy is stored/released when making/breaking ATP?
30 KJ/mol
Chemiosmosis
the coupling of ion electrochemical gradients to cellular work
e.g. H+ electrochemical gra. with ATP synthesis
How do you measure quantifiable stores of potential energy?
Measure ion electrochemical gradients
Faraday constant
gives energy related to moving the charge associated with 1 mol of H+ across electrical gradient of 1 volt
Formula:
Electrochemical potential =
Electrical potential gradient + chemical potential gradient
Electrochemical potential
total energy stored across the membrane with respect to translocation of SZO to SZI
How do you convert to K from degrees centigrade?
add 273
What proof is there of chemiosmotic coupling?
~ add an uncoupler to a double-membrane vesicle with e- transport chain and ATP synthase
~ heat is created –> H+ ions pass through uncoupler
~ no ATP made
What natural examples are there of uncouplers in chemiosmosis?
non-shivering thermogenesis by brown adipose tissue - they use uncouplers to make heat
~ membrane is made permeable to H+ ions
Name an uncoupler.
DiNitroPhenol (DNP) - a protonophore
~ used as illegal weight-loss pills
Redox potential
more -ve the value, the lower the substance has for e- and so willingly donates in reduced form
Complexes
groups of redox couples/centers
oxidation of 1 glucose = … ATP
38 ATP
Net ATP production in glycolysis is …
2
Net ATP production in citric acid cycle is …
2 (made from GTP)
