The Aspergillus niger Major Allergen (Asp n 3) DNA-Specific Sequence Is a Reliable Marker to Identify Early Fungal Contamination and Postharvest Damage in Mangifera indica Fruit

Abstract

The aim of this work was to study the value of the main allergen Asp n 3 of Aspergillus niger as a molecular marker of allergenicity and pathogenicity with the potential to be used in the identification of A. niger as a contaminant and cause of spoilage of Mangifera indica. Real-time polymerase chain reaction (RT-PCR) was used for the amplification of Asp n 3 gene. Two pairs of primers were designed: one for the amplification of the entire sequence and another one for the amplification of the most conserved region of this peroxisomal protein. The presence of A. niger was demonstrated by the early detection of the allergenic protein Asp n 3 coding gene, which could be considered a species-specific marker. The use of primers designed based on the conserved region of the Asp n 3 encoding gene allowed us to identify the presence of the closely related fungal species Aspergillus fumigatus by detecting Asp n 3 homologous protein, which can be cross-reactive. The use of conserved segments of the Asp n 3 gene or its entire sequence allows us to detect phylogenetically closely related species within the Aspergilaceae family or to identify species-specific contaminating fungi.

Isolation, Identification, and Polymerase Chain Reaction Analysis of Pathogenic Fungi in Sweet Orange (Citrus sinensis L.) Fruits during Storage

“…This could be due to the presence of their spores, which released toxins into the oranges which resulted in the deterioration at storage. Contrary to the findings of this research, it was previously reported that P. spp were the most important economic pathogens of sweet oranges during storage. , R. pusillus was the organism with the least incidence in this study. The least incidence of M. spp .…”

“…Contrary to the findings of this research, it was previously reported that P. spp were the most important economic pathogens of sweet oranges during storage. 30,34 R. pusillus was the organism with the least incidence in this study. The least incidence of M. spp.…”

Fungal Allergen and Mold Allergy Diagnosis: Role and Relevance of Alternaria alternata Alt a 1 Protein Family

“…The development of DNA technology has provided effective methods for the study of different fungi, and several genetic markers have been provided for their identification. These markers are widely used in PCR or chip detection [ 84 ]. In recent years, multigene phylogeny has been widely employed for the identification and characterization of Alternaria species.…”

“…Recently, some fungal allergens (Alt a 1 and Asp n 3) have been presented as valuable molecular markers of taxonomy and pathology/contamination in vegetables and fruits and also as molecular markers of allergenic contamination in indoor environments [ 4 , 84 , 91 ].…”

“…Gabriel et al, using primers defining the Alt a 1 encoding gen (390 bp) and the conserved region of Alt a 1 encoding gen (180 bp) from A. alternata , were able to detect the infection of citrus fruits by A. alternata at the onset of infection [ 84 ]. The conserved region was able to detect Alt a 1 homologs in several species of Alternaria section, but the fragment encoding of the Alt a 1 gen (390 bp) only detected A. alternata and A. tenuissima .…”