Intracellular pH responses in the industrially important fungus Trichoderma reesei

Mari Valkonen*, Merja Penttila, Mojca Bencina

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

Abstract

Preserving an optimal intracellular pH is critical for cell fitness and productivity. The pH homeostasis of the industrially important filamentous fungus Trichoderma reesei (Hypocrea jecorina) is largely unexplored. We analyzed the impact of growth conditions on regulation of intracellular pH of the strain Rut-C30 and the strain M106 derived from the Rut-C30 that accumulates L-galactonic acid from provided galacturonic acid as a consequence of L-galactonate dehydratase deletion. For live-cell measurements of intracellular pH, we used the genetically encoded ratiometric pH-sensitive fluorescent protein RaVC. Glucose and lactose, used as carbon sources, had specific effects on intracellular pH of T. reesei. The growth in lactose-containing medium extensively acidified cytosol, while intracellular pH of hyphae cultured in a medium with glucose remained at a higher level. The strain M106 maintained higher intracellular pH in the presence of D-galacturonic acid than its parental strain Rut-C30. Acidic external pH caused significant acidification of cytosol. Altogether, the pH homeostasis of T. reesei Rut-C30 strain is sensitive to extracellular pH and the degree of acidification depends on carbon source. (C) 2014 Elsevier Inc. All rights reserved.

Original languageEnglish
Pages (from-to)86-93
Number of pages8
JournalFungal Genetics and Biology
Volume70
DOIs
Publication statusPublished - Sep 2014
MoE publication typeA1 Journal article-refereed

Keywords

  • Genetically encoded pH sensor RaVC
  • Ratiometric indicator
  • pH homeostasis
  • Filamentous fungus Trichoderma reesei
  • Dual sequential scanning microscopy
  • D-GALACTURONIC ACID
  • SACCHAROMYCES-CEREVISIAE
  • HYPOCREA-JECORINA
  • CELLULASE PRODUCTION
  • ASPERGILLUS-NIGER
  • FILAMENTOUS FUNGI
  • D-XYLOSE
  • VESICLE TRAFFICKING
  • BETA-GALACTOSIDASE
  • FLOW-CYTOMETRY

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