Indicate whether each of the following descriptions matches an ABC transporter (A), a P-type pump (P), or a V-type pump (V). Your answer would be a five-letter string composed of letters A, P, and V only, e.g. PPVVV.
( ) The pumps in this family are phosphorylated at a key Asp residue in each transport cycle.
( ) This family is the largest among membrane transport proteins and includes some channels as well as pumps.
( ) The pumps in this family are responsible for the acidification of synaptic vesicles.
( ) The sodium-potassium pump is a member of this family.
( ) The multidrug resistance protein is a member of this family.

Question

Indicate whether each of the following descriptions matches an ABC transporter (A), a P-type pump (P), or a V-type pump (V). Your answer would be a five-letter string composed of letters A, P, and V only, e.g. PPVVV.
( )	The pumps in this family are phosphorylated at a key Asp residue in each transport cycle.
( )	This family is the largest among membrane transport proteins and includes some channels as well as pumps.
( )	The pumps in this family are responsible for the acidification of synaptic vesicles.
( )	The sodium-potassium pump is a member of this family.
( )	The multidrug resistance protein is a member of this family.

Quizplus · Accepted Answer

P-type pumps (e.g. the Na?-K? pump) phosphorylate a key aspartic acid residue of their phosphorylation domain in each transport cycle. The ABC superfamily is the largest among membrane transport protein families and is of great clinical importance, as exemplified by the multidrug resistance (MDR) protein. Vesicle acidification is normally performed by V-type ATPases.

Indicate Whether Each of the Following Descriptions Matches an ABC