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Strain-specific polyketide synthase genes of Aspergillus niger
Lara Munique Ferracin1, Carla Beatriz Fier, Maria Lucia Carneiro Vieira
1Universidade Estadual de Londrina, Centro de Ciências Biológicas, P.O. Box 6001, 86051-990 Londrina, Brazil.
International Journal of Food Microbiology
|February 21, 2012
Summary
Genetic analysis of Aspergillus niger reveals strain-specific polyketide synthase (pks) genes. One pks gene linked to ochratoxin production shows a strong association with mycotoxin capability in various strains.
Area of Science:
- Genomics
- Mycology
- Biotechnology
Background:
- Aspergillus niger is a versatile fungus with significant industrial and agricultural relevance.
- Polyketide synthases (pks) are crucial enzymes involved in secondary metabolite production, including mycotoxins.
- Understanding genetic variability in pks genes is key to predicting fungal traits.
Purpose of the Study:
- To compare putative polyketide synthase (pks) genes between Aspergillus niger strains using in silico and in vivo methods.
- To identify strain-specific pks genes and investigate their association with ochratoxin production.
- To validate bioinformatics predictions with experimental data.
Main Methods:
- In silico comparative genomics of pks genes in A. niger strains CBS 513.88 and ATCC 1015.
- Experimental validation using PCR and Southern blot analysis on 119 A. niger strains.
- Assessment of ochratoxin production capability in A. niger strains.
Main Results:
- 31 out of 34 putative pks genes showed high nucleotide identity (>95%) between the two A. niger strains.
- Three pks genes (An01g01130, An11g05940, An15g07920) were identified as strain-specific.
- The presence of the strain-specific pks gene An15g07920 was positively associated with ochratoxin production capability.
Conclusions:
- Bioinformatic analysis effectively predicts strain-specific pks genes in Aspergillus niger.
- Strain-specific pks genes contribute to phenotypic variation, such as mycotoxin production.
- The pks gene An15g07920 is a potential marker for ochratoxin production in A. niger.
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