Lectures 21 & 22 Part Five

Front

What are integral proteins with 8 or 10 predicted membrane-spanning regions sensitive to?

Back

They are sensitive to inhibition by the transition-state analog vanadate.

Front

What is the function of Na+ K+ ATPase in animal cells?

Back

Na+ K+ ATPase is an antiporter for Na+ and K+, maintaining low [Na+] and high [K+] in the cell, essential for action potentials in neurons.

Front

What is the role of H+ ATPase in plants and fungi?

Back

H+ ATPase functions as a transporter in plants and fungi.

Front

What is the function of the sarcoplasmic/endoplasmic reticulum Ca2+ ATPase (SERCA) pump?

Back

The SERCA pump is a uniporter for Ca2+ ions.

Front

What is the general structure of P-Type ATPases?

Back

They have a critical Asp residue in the P domain that undergoes phosphorylation and dephosphorylation.

Front

What is the postulated mechanism of the SERCA pump?

Back

Each catalytic cycle moves two Ca2+ ions across the membrane and converts an ATP to ADP and Pi, with two conformations, E1 and E2, interconverting.

Front

What are V-Type ATPases responsible for?

Back

V-Type ATPases are responsible for acidifying intracellular compartments.

Front

What is the function of F-Type ATPases?

Back

F-Type ATPases catalyze the uphill transmembrane passage of protons, driven by ATP hydrolysis.

Front

What is the role of ABC transporters?

Back

ABC transporters use ATP to drive the active transport of a wide variety of substrates across a membrane against a concentration gradient.

Front

What is the mechanism of ABC transporters?

Back

Substrates move across the membrane when two forms of the transporter interconvert, driven by ATP hydrolysis.