Targeting a polyketide synthase gene for Aspergillus carbonarius quantification and ochratoxin A assessment in grapes using real-time PCR.
Aspergillus carbonarius is an ochratoxin producing fungus that has been considered to be responsible of the ochratoxin A (OTA) contamination in grapes and wine. In order to monitor and quantify A. carbonarius, a specific primer pair Ac12RL_OTAF/Ac12RL_OTAR has been designed from the acyltransferase (AT) domain of the polyketide synthase sequence Ac12RL3 to amplify 141 bp PCR product. Among the mycotoxigenic fungi tested, only A. carbonarius gave a positive result. This specific primer pair was also successfully employed in real-time PCR conjugated with SYBR Green I dye for the direct quantification of this fungus in grape samples. A positive correlation (R(2)=0.81) was found between A. carbonarius DNA content and OTA concentration in 72 grape samples, allowing for the estimation of the potential risk from OTA contamination. Consequently, this work offers a quick alternative to conventional methods of OTA quantification and mycological detection and quantification of A. carbonarius in grapes.
Atoui
Ali
A
Département Bioprocédés et Systèmes Microbiens, Laboratoire de Génie Chimique UMR5503, Ecole Nationale Supérieure Agronomique de Toulouse, Institut National Polytechnique de Toulouse, 1, avenue de l'Agrobiopôle, BP32607, 31326 Castanet Tolosan, France.
Mathieu
Florence
F
Lebrihi
Ahmed
A
D001230:Aspergillus / Q000201:enzymology*; D003257:Consumer Product Safety; D017931:DNA Primers; D004271:DNA, Fungal / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis; D005516:Food Microbiology; D005784:Gene Amplification; D009793:Ochratoxins / Q000096:biosynthesis*; D048630:Polyketide Synthases / Q000235:genetics*; D016133:Polymerase Chain Reaction / Q000379:methods; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D027843:Vitis / Q000382:microbiology*
D017931:DNA Primers; D004271:DNA, Fungal; D009793:Ochratoxins; C025589:ochratoxin A; D048630:Polyketide Synthases