Bio270 September 26, 2012
o Reducing energy
o Redox Status
High Energy Bonds
o ATP is stored in a stable level in cells. 5mM in muscle cells
o High AcetylCoA = High energy in cells
Mito Oxidative Metabolism
o AcetylCoA is the main point of entry for mitochondrial energy producing pathways.
o 1 gtp is equivalent of 1 atp molecule
o Amphibolic pathway = anabolic and catabolic
o Series of redox reactions as electrons are passed from one place to another.
o 3 complexes use energy from oxidation of nadh and nadh2 from the protons to pump
energy, in order to produce ATP from ADP-Phosphorylation.
o Link through proto-motive force and not physically link.
Integration of Metabolic Pathways
o ATP and oxygen is needed for energy to utilize from mitochondria.
o High energy stimulates anabolic pathways, while low energy stimulates catabolic
o Glyco-lipids are found outside of the membrane
o Amphipatic – both hydrophilic and hydrophobic
Liquid profile affects membrane properties
o Cholesterol – enhances fluidity at low temperature, while inhibits fluidity at high
If both molecules are squeezed together, Van der waals force increases.
o Lipid rafts
Temp and membrane fluidity
o Cold temperature increase van der waals forces between lipids and restrict movement,
while warm temperature decreases van der waals forces and causes movement.
o Two types Integral – pass completely to membrane called transmembrane proteins. Not all
of them are tmp, it can be embedded only to it. Tmp are amphiphatic.
Peripheral - weak bonds and not embedded on the membrane.
o Lipid soluble solute can pass through the membrane (passive diffusion).
o Facilitated Diffusion
Channel is like a gate passage
Permease is like an enzyme
o High concentration to low concentration movement. No energy is required.
o Active transport
o No energy needed.
o Net flow from high concentration to low concentration.
o No specific transporters needed.
o No energy required but protein transporter needed.
o 3 Protein carriers
Ion channels gated channels
Porins like ion channels but for larger molecules.
Permeases acts like an enzyme, has affinity constant. A conformational
change causes the channeling to occur.
o 3 types
Voltage gated – change of voltage across the membrane leading to opening of
the gate. Eg. Potassium channel
Ligand gated – binds to channel and opens ga