title: Species-specific optical genosensors for the detection of mycotoxigenic Fusarium fungi in food samples.
abstract: Plant-pathogenic Fusarium species, Fusarium verticillioides and Fusarium proliferatum, are the major producers of fumonisins which are one of the most common mycotoxins found in maize. Herein, we report the development of specific and sensitive genosensors for detecting these two closely related Fusarium species in food samples. The sensors are based on species-specific capture and detection probes, which bind to the intergenic spacer region of rDNA (IGS). Oligonucleotide functionalized magnetic microbeads are used to capture the target DNA which is then detected using biotinylated detection probes and a streptavidin-coupled label. The developed genosensors had detection limits of 1.8 pM and 3.0 pM for F. proliferatum and F. verticillioides, respectively, using synthetic DNA targets. Furthermore, the biosensors were used to analyze natural fungal contamination of commercial maize samples. After amplification of the genomic DNA the sensors detected the presence of the fungi, in accordance with previous results obtained with PCR. No cross-reactivity between F. verticillioides and F. proliferatum, or other fungi species tested, was observed. The developed biosensors can provide a valuable tool to evaluate the potential for mycotoxin contamination in conditions where detection of mycotoxins directly is challenging.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Complutense University, Ciudad Universitaria s/n, Madrid 28040, Spain.
authors.forename: Riikka
authors.initials: R
authors.lastname: Peltomaa
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Complutense University, Ciudad Universitaria s/n, Madrid 28040, Spain.
authors.forename: Silvia
authors.initials: S
authors.lastname: Vaghini
authors.affiliation: Department of Microbiology III, Faculty of Biology, Complutense University, Ciudad Universitaria s/n, Madrid 28040, Spain.
authors.forename: Belén
authors.initials: B
authors.lastname: Patiño
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Complutense University, Ciudad Universitaria s/n, Madrid 28040, Spain. Electronic address: elenabp@ucm.es.
authors.forename: Elena
authors.initials: E
authors.lastname: Benito-Peña
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Complutense University, Ciudad Universitaria s/n, Madrid 28040, Spain. Electronic address: mcmbondi@ucm.es.
authors.forename: María C
authors.initials: MC
authors.lastname: Moreno-Bondi
mesh_terms: D015374:Biosensing Techniques; D004271:DNA, Fungal / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis*; D005670:Fusarium / Q000737:chemistry*; D009183:Mycotoxins / Q000032:analysis*; D013045:Species Specificity; D003313:Zea mays / Q000737:chemistry / Q000382:microbiology
chemical_list: D004271:DNA, Fungal; D009183:Mycotoxins
keywords: Fusarium; Hybridization assay; Intergenic spacer region; Magnetic microbeads