The regulatory domain of fungal and plant plasma membrane H(+)-ATPase.
The activity of fungal and plant plasma membrane H(+)-ATPases seems to be regulated by modulation of the interaction of an inhibitory domain at the C-terminus with the active site. In the yeast ATPase, a mutation at the active site (Ala547- > Val) and a deletion of the C-terminus result in constitutive activation. A double Ser911- > Ala, Thr912- > Ala mutation at the C-terminus (defining putative phosphorylation sites) locks the enzyme in the inhibited state and can be suppressed by the Ala547- > Val mutation at the active site. This provides genetic evidence for domain interaction. In plant ATPase, proteolytic removal of the C-terminus also results in constitutive activation. A peptide covering a region of the plant C-terminus with homology to the yeast C-terminus inhibits the truncated plant ATPase. This suggests similar regulatory mechanisms in fungal and plant ATPases.
Serrano
R
R
European Molecular Biology Laboratory, Heidelberg, Germany.
Portillo
F
F
Monk
B C
BC
Palmgren
M G
MG
D002462:Cell Membrane / Q000201:enzymology*; D005658:Fungi / Q000201:enzymology*; D010944:Plants / Q000201:enzymology*; D006180:Proton-Translocating ATPases / Q000378:metabolism*
D006180:Proton-Translocating ATPases