Haloadaptative responses of Aspergillus sydowii to extreme water deprivation : morphology, compatible solutes, and oxidative stress at NaCl saturation

Jiménez-Gómez, Irina (author), Valdés-Muñoz, Gisell (author), Moreno-Perlín, Tonatiuh (author), Mouriño-Pérez, Rosa R. (author), Rayo Sánchez-Carbente, María del (author), Folch-Mallol, Jorge Luis (author), Pérez-Llano, Yordanis (author), Gunde-Cimerman, Nina (author), C. Sánchez, Nilda del (author), Batista-García, Ramón Alberto (author)

Water activity (a$_w$) is critical for microbial growth, as it is severely restricted at a$_w$ < 0.90. Saturating NaCl concentrations (~5.0 M) induce extreme water deprivation (aw ≅ 0.75) and cellular stress responses. Halophilic fungi have cellular adaptations that enable osmotic balance and ionic/oxidative stress prevention to grow at high salinity. Here we studied the morphology, osmolyte synthesis, and oxidative stress defenses of the halophile Aspergillus sydowii EXF-12860 at 1.0 M and 5.13 M NaCl. Colony growth, pigmentation, exudate, and spore production were inhibited at NaCl-saturated media. Additionally, hyphae showed unpolarized growth, lower diameter, and increased septation, multicellularity and branching compared to optimal NaCl concentration. Trehalose, mannitol, arabitol, erythritol, and glycerol were produced in the presence of both 1.0 M and 5.13 M NaCl. Exposing A. sydowii cells to 5.13 M NaCl resulted in oxidative stress evidenced by an increase in antioxidant enzymes and lipid peroxidation biomarkers. Also, genes involved in cellular antioxidant defense systems were upregulated. This is the most comprehensive study that investigates the micromorphology and the adaptative cellular response of different non-enzymatic and enzymatic oxidative stress biomarkers in halophilic filamentous fungi.

• Language: English
• Keywords: Aspergillus sydowii, halophily, extremophilic fungi, saline stress, saturated NaCl solution, water deprivation, oxidative stress, morphology
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: BF - Biotechnical Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2020
• Number of pages: 20 str.
• Numbering: Vol. 6, iss. 4, art. 316
• PID: 20.500.12556/RUL-134689
• UDC: 577
• ISSN on article: 2309-608X
• DOI: 10.3390/jof6040316
• COBISS.SI-ID: 46917379
• Publication date in RUL: 26.01.2022

Record is a part of a journal

• Title: Journal of Fungi
• Shortened title: J. Fungi
• Publisher: MDPI
• ISSN: 2309-608X
• COBISS.SI-ID: 525300761

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 01.12.2020

Secondary language

• Language: Slovenian
• Keywords: biokemija, glive, oksidativni stres, morfologija