Lecture 12 Flashcards
Electron Transport Chain
couples electron transfer between an electron donor and an electron acceptor with the transfer of H+ ions across a membrane
Terminal Electron Acceptor (TEA)
A compound that accepts an electron during oxidation of carbon sourc
Electron Carrier
A molecule capable of accepting one (or more than one) electrons from another molecule (electron donor), and then ferry these electrons to donate to another during the process of electron transport.
NAD
a coenzyme found in all living cells. The compound is a dinucleotide, since it consists of two nucleotides joined through their phosphate groups
FAD
a redox cofactor involved in several important reactions in metabolism. FAD can exist in two different redox states, which it converts between by accepting or donating electrons
Quinol/ Quinone
Sites in the Q-loop where protons go to cross the membrane
FeS Protein
proteins characterized by the presence of iron-sulfur clusters containing sulfide-linked di-, tri-, and tetrairon centers in variable oxidation states.
Heme (cytochrome)
membrane-bound hemeproteins containing heme groups and are primarily responsible for the generation of ATP via electron transport.
Q-loop
Proton pump in complex III due to the Q-loop. Protons cross the membrane
Chemiosmosis
the movement of ions across a selectively permeable membrane, down their electrochemical gradient. Used to make ATP
Oxidative Phosphorylation
the metabolic pathway in which the mitochondria in cells use their structure, enzymes, and energy released by the oxidation of nutrients to reform ATP
Mitchell Hypothesis
CHEMIOSMOTIC HYPOTHESIS in 1961. The theory suggests that most ATP synthesis in respiring cells comes from the electrochemical gradient across the inner membranes of mitochondria by using the energy of NADH and FADH2 formed from the breaking down of energy-rich molecules, such as glucose.
ATP Synthase
The proton gradient is used to make ATP
Substrate-level phosphorylation
a type of metabolic reaction that results in the formation of adenosine triphosphate (ATP) or guanosine triphosphate (GTP) by the direct transfer and donation of a phosphoryl (PO3) group to adenosine diphosphate (ADP) or guanosine diphosphate (GDP) from a phosphorylated reactive intermediate.
Cytochrome C Oxidase
a large transmembrane protein complex found in bacteria and the mitochondrion. Complex IV