Title:Proteomic Analysis of Intra- and Extracellular Proteins of Aspergillus Niveus During Submerged Bioprocess Culturing Under Different pH Conditions
Volume: 18
Issue: 4
Author(s): Juliana Abigail Leite, Nathalia Gonsales da Rosa-Garzon, Helen Julie Laure, José Cesar Rosa, Octavio Luiz Franco, Cristina Maria de Souza Motta and Hamilton Cabral*
Affiliation:
- Department of Pharmaceutical Sciences, School of Pharmaceutical Sciences of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto,Brazil
Keywords:
Aspergillu niveus, MALDI-TOF/TOF-MS, pH effect, proteomic, secretome, submerged bioprocess.
Abstract:
Background: Proteomics facilitates understanding the complexity of molecular and physiological
mechanisms involved in the metabolic and biological fungal adaptations to pH changes.
Proteomics enables the identification of enzymes and fungal proteins involved in these adaptations.
This approach may be used to investigate such fungi as Aspergillus niveus, whose proteome has
not yet been analyzed, changes the intra- and extracellular protein profiles in response to extracellular
pH.
Objective: In the current study, we used two-dimensional gel electrophoresis (2DE) and mass spectrometry
to evaluate the response of A. niveus to grow at pH 5, 6, 7, and 8 for 96 hours submerged
bioprocess culturing.
Methods: This study evaluated the response of A. niveus to grow at pH 5, 6, 7, and 8 for 96 h submerged
bioprocess culturing, by analysis of two-dimensional gel electrophoresis (2DE), of the intracellular
proteomes and the secretome, protein spots of interest were submitted to tryptic digestion
and analyzed by matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry
(MALDI-TOF/TOF-MS).
Results: This approach revealed substantial differences between the functions of intra- and extracellular
proteins of A. niveus. The data suggested that pH-modulated global proteins are involved in
important, mainly metabolic, processes, in the pentose phosphate pathway, protein regulation, cell
wall maintenance, and others. Moreover, the change in extracellular pH could have altered the availability
of nutrients, and induced the production of enzymes that respond to oxidative and other
stresses.
Conclusion: Proteomic facilitates understanding of the complexity of molecular and physiological
mechanisms involved in the metabolic and biological adaptations of fungi to pH changes.
