SGD Paper Help



Petrov VV, et al.  (2000) Functional role of charged residues in the transmembrane segments of the yeast plasma membrane H+-ATPase. J Biol Chem 275(21):15709-16

Abstract: As defined by hydropathy analysis, the membrane-spanning segments of the yeast plasma membrane H(+)-ATPase contain seven negatively charged amino acids (Asp and Glu) and four positively charged amino acids (Arg and His). To explore the functional role of these residues, site-directed mutants at all 11 positions and at Glu-288, located near the cytoplasmic end of M3, have been constructed and expressed in yeast secretory vesicles. Substitutions at four of the positions (Glu-129, Glu-288, Asp-833, and Arg-857) had no significant effect on ATP hydrolysis or ATP-dependent proton pumping, substitutions at five additional positions (Arg-695, His-701, Asp-730, Asp-739, and Arg-811) led to misfolding of the ATPase and blockage at an early stage of biogenesis, and substitutions of Asp-143 allowed measurable biogenesis but nearly abolished ATP hydrolysis and proton transport. Of greatest interest were mutations of Glu-703 in M5 and Glu-803 in M8, which altered the apparent coupling between hydrolysis and transport. Three Glu-703 mutants (E703Q, E703L, E703D) showed significantly reduced pumping over a wide range of hydrolysis values and thus appeared to be partially uncoupled. At Glu-803, by contrast, one mutant (E803N) was almost completely uncoupled, while another (E803Q) pumped protons at an enhanced rate relative to the rate of ATP hydrolysis. Both Glu-703 and Glu-803 occupy positions at which amino acid substitutions have been shown to affect transport by mammalian P-ATPases. Taken together, the results provide growing evidence that residues in membrane segments 5 and 8 of the P-ATPases contribute to the cation transport pathway and that the fundamental mechanism of transport has been conserved throughout the group.

Status: Published Type: Journal Article PubMed ID: 10747929

Topics addressed in this paper

  • To find other papers on a gene and topic, click on the colored ball in the appropriate box.
  • displays other papers with information about that topic for that gene.
  • displays other papers in SGD that are associated with that topic.
    The topic is addressed in these papers but does not describe a specific gene or chromosomal feature.
  • To go to the Locus page for a gene, click on the gene name.
Topics Genes linked to topics
PMA1
Function/Process blue ball
Mutants/Phenotypes blue ball
Primary Literature blue ball
Protein Physical Properties blue ball
Protein Sequence Features blue ball
Strains/Constructs blue ball

Author Searches

To find contact information or other publications by the authors of this paper, follow these three steps:
  1. (1) Choose an author,
  2. (2) Choose a search parameter,
  3. (3) Click to implement