A Study of the Expression of Aflatoxin B1 Regulatory Gene in Clinical and Environmental Aspergillus flavus using Real-time PCR

Batol Imran Dheeb, Eman Noaman Ismail, Ibrahim I. Hassan AL-mishhadani, Suad M. Majeed, Duha Mysire Majeed


This recent study investigated the differences in the expression of Aflatoxin B1 regulatory gene among clinical and environmental (Aspergillus flavus) isolates. Samples were subjected to RNA isolation, cDNA synthesis and PCR amplification. Electrophoresis demonstrated clean bands 798 bp upon amplification with aflR1 primers. The ability of A. flavus confirmed the presence of the aflR2 gene in product size 400 bp in all the studied isolates with a different gene expression (Sentence not clear. Rephrase). There was a direct correlation between the aflr gene expression and the isolates source. The source of isolates significantly influenced the aflr gene expression. It appeared that the aflr gene expression increased at the A. flavus isolated from patients with aspergillosis with a gradual gene expression in A. flavus isolated from grains of Zea mays (maize) and with no clear expression in the A. flavus isolated from rice grain. These results indicate a suitable molecular method for detecting and controlling the spread of A. flavus in the grainer and in hospitals to avoid infection.


Aspergillus flavus; Aflatoxin B1; gene expression; aflR

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