Applied Microbiology and Biotechnology

, Volume 99, Issue 20, pp 8667–8680

PEP3 overexpression shortens lag phase but does not alter growth rate in Saccharomyces cerevisiae exposed to acetic acid stress

  • Jun Ding
  • Garrett Holzwarth
  • C. Samuel Bradford
  • Ben Cooley
  • Allen S. Yoshinaga
  • Jana Patton-Vogt
  • Hagai Abeliovich
  • Michael H. Penner
  • Alan T. Bakalinsky
Applied microbial and cell physiology

DOI: 10.1007/s00253-015-6708-9

Cite this article as:
Ding, J., Holzwarth, G., Bradford, C.S. et al. Appl Microbiol Biotechnol (2015) 99: 8667. doi:10.1007/s00253-015-6708-9

Abstract

In fungi, two recognized mechanisms contribute to pH homeostasis: the plasma membrane proton-pumping ATPase that exports excess protons and the vacuolar proton-pumping ATPase (V-ATPase) that mediates vacuolar proton uptake. Here, we report that overexpression of PEP3 which encodes a component of the HOPS and CORVET complexes involved in vacuolar biogenesis, shortened lag phase in Saccharomyces cerevisiae exposed to acetic acid stress. By confocal microscopy, PEP3-overexpressing cells stained with the vacuolar membrane-specific dye, FM4-64 had more fragmented vacuoles than the wild-type control. The stained overexpression mutant was also found to exhibit about 3.6-fold more FM4-64 fluorescence than the wild-type control as determined by flow cytometry. While the vacuolar pH of the wild-type strain grown in the presence of 80 mM acetic acid was significantly higher than in the absence of added acid, no significant difference was observed in vacuolar pH of the overexpression strain grown either in the presence or absence of 80 mM acetic acid. Based on an indirect growth assay, the PEP3-overexpression strain exhibited higher V-ATPase activity. We hypothesize that PEP3 overexpression provides protection from acid stress by increasing vacuolar surface area and V-ATPase activity and, hence, proton-sequestering capacity.

Keywords

Saccharomyces cerevisiae Yeast Acetic acid PEP3 V-ATPase HOPS CORVET Vacuole STM1 PEP5 

Supplementary material

253_2015_6708_MOESM1_ESM.pdf (896 kb)
ESM 1(PDF 895 kb)

Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Jun Ding
    • 1
    • 2
  • Garrett Holzwarth
    • 2
    • 3
  • C. Samuel Bradford
    • 4
  • Ben Cooley
    • 5
  • Allen S. Yoshinaga
    • 2
    • 3
  • Jana Patton-Vogt
    • 5
  • Hagai Abeliovich
    • 6
  • Michael H. Penner
    • 2
  • Alan T. Bakalinsky
    • 1
    • 2
    • 3
  1. 1.Department of Biochemistry and BiophysicsOregon State UniversityCorvallisUSA
  2. 2.Department of Food Science and TechnologyOregon State UniversityCorvallisUSA
  3. 3.Department of MicrobiologyOregon State UniversityCorvallisUSA
  4. 4.Department of Environmental & Molecular ToxicologyOregon State UniversityCorvallisUSA
  5. 5.Biological SciencesDuquesne UniversityPittsburghUSA
  6. 6.Department of Biochemistry and Food ScienceHebrew UniversityRehovotIsrael