1
|
Zhu Z, Yang M, Bai Y, Ge F, Wang S. Antioxidant-related catalase CTA1 regulates development, aflatoxin biosynthesis, and virulence in pathogenic fungus Aspergillus flavus. Environ Microbiol 2020; 22:2792-2810. [PMID: 32250030 DOI: 10.1111/1462-2920.15011] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 03/17/2020] [Accepted: 03/31/2020] [Indexed: 11/29/2022]
Abstract
Reactive oxygen species (ROS) induce the synthesis of a myriad of secondary metabolites, including aflatoxins. It raises significant concern as it is a potent environmental contaminant. In Aspergillus flavus., antioxidant enzymes link ROS stress response with coordinated gene regulation of aflatoxin biosynthesis. In this study, we characterized the function of a core component of the antioxidant enzyme catalase (CTA1) of A. flavus. Firstly, we verified the presence of cta1 corresponding protein (CTA1) by Western blot analysis and mass-spectrometry based analysis. Then, the functional study revealed that the growth, sporulation and sclerotia formation significantly increased, while aflatoxins production and virulence were decreased in the cta1 deletion mutant as compared with the WT and complementary strains. Furthermore, the absence of the cta1 gene resulted in a significant rise in the intracellular ROS level, which in turn added to the oxidative stress level of cells. A further quantitative proteomics investigation hinted that in vivo, CTA1 might maintain the ROS level to facilitate the aflatoxin synthesis. All in all, the pleiotropic phenotype of A. flavus CTA1 deletion mutant revealed that the antioxidant system plays a crucial role in fungal development, aflatoxins biosynthesis and virulence.
Collapse
Affiliation(s)
- Zhuo Zhu
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Mingkun Yang
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.,State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Youhuang Bai
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Feng Ge
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Shihua Wang
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| |
Collapse
|
2
|
Sun X, Su X. Harnessing the knowledge of protein secretion for enhanced protein production in filamentous fungi. World J Microbiol Biotechnol 2019; 35:54. [PMID: 30900052 DOI: 10.1007/s11274-019-2630-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 03/08/2019] [Indexed: 12/19/2022]
Abstract
Filamentous fungi are important microorganisms used in industrial production of proteins and enzymes. Among these organisms, Trichoderma reesei, Aspergilli, and more recently Myceliophthora thermophile are the most widely used and promising ones which have powerful protein secretion capability. In recent years, there have been tremendous achievements in understanding the molecular mechanisms of the secretory pathways in filamentous fungi. The acquired pieces of knowledge can be harnessed to enhance protein production in filamentous fungi with assistance of state-of-the-art genetic engineering techniques.
Collapse
Affiliation(s)
- Xianhua Sun
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 South Zhongguancun Street, Beijing, 100081, China
| | - Xiaoyun Su
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 South Zhongguancun Street, Beijing, 100081, China.
| |
Collapse
|
3
|
Giles SS, Stajich JE, Nichols C, Gerrald QD, Alspaugh JA, Dietrich F, Perfect JR. The Cryptococcus neoformans catalase gene family and its role in antioxidant defense. EUKARYOTIC CELL 2006; 5:1447-59. [PMID: 16963629 PMCID: PMC1563583 DOI: 10.1128/ec.00098-06] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In the present study, we sought to elucidate the contribution of the Cryptococcus neoformans catalase gene family to antioxidant defense. We employed bioinformatics techniques to identify four members of the C. neoformans catalase gene family and created mutants lacking single or multiple catalase genes. Based on a phylogenetic analysis, CAT1 and CAT3 encode putative spore-specific catalases, CAT2 encodes a putative peroxisomal catalase, and CAT4 encodes a putative cytosolic catalase. Only Cat1 exhibited detectable biochemical activity in vitro, and Cat1 activity was constitutive in the yeast form of this organism. Although they were predicted to be important in spores, neither CAT1 nor CAT3 was essential for mating or spore viability. Consistent with previous studies of Saccharomyces cerevisiae, the single (cat1, cat2, cat3, and cat4) and quadruple (cat1 cat2 cat3 cat4) catalase mutant strains exhibited no oxidative-stress phenotypes under conditions in which either exogenous or endogenous levels of reactive oxygen species were elevated. In addition, there were no significant differences in the mean times to mortality between groups of mice infected with C. neoformans catalase mutant strains (the cat1 and cat1 cat2 cat3 cat4 mutants) and those infected with wild-type strain H99. We conclude from the results of this study that C. neoformans possesses a robust antioxidant system, composed of functionally overlapping and compensatory components that provide protection against endogenous and exogenous oxidative stresses.
Collapse
Affiliation(s)
- Steven S Giles
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | | | | | | | | | | | | |
Collapse
|