Selection and characterization of single stranded DNA aptamers recognizing fumonisin B1
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We present an improved method for the selection of single-stranded DNA aptamers that can recognize fumonisin B1 (FB1). FB1 is a carcinogenic mycotoxin mainly found in corn and corn-based food products worldwide, posing a global threat to feed and food safety. Selection was based on the mag-SELEX (magnetic bead systematic evolution of ligands by exponential enrichment) technology modified by adopting free analogs of targets rather than immobilized targets for counter selections. Firstly, aptamer candidates for FB1 were selected from an 80 nt random DNA library after 13 rounds of selection. Next, binding assays were performed for affinity evaluation, and circular dichroism spectroscopy was used to investigate their conformation. A high-affinity aptamer designated as F10 (with a dissociation constant of 62 ± 5 nM) was identified and tested for its specificity by competitive binding assays. The results demonstrate that this improved mag-SELEX technology facilitates aptamer screening because it avoids the tedious immobilization of counter-selection molecules on magnetic beads. The aptamers obtained by this technique open new possibilities for the detection of FB1 via aptasensors.
KeywordsFumonisin B1 Aptamer SELEX Magnetic beads Competition
This work was partly supported by NSFC (21375049), National S&T Support Program of China (2012BAK08B01), S&T Supporting Project of Jiangsu Province (BE2011621, BE2012614), Research Fund for the Doctoral Program of Higher Education (20110093110002), NCET-11-0663, JUSRP51309A and JUSRP21125.
- 1.Ross PF, Nelson PE, Richard JL, Osweiler GD, Rice LG, Plattner RD (1990) Production of fumonisins by Fusarium moniliforme and Fusarium proliferatum isolates associated with equine leukoencephalomalacia and a pulmonary edema syndrome in swine. Appl Environ Microbiol 56:3225–3226Google Scholar
- 3.Mallmann CA, Santurio JM, Almeida CAA, Dilkin P (2001) Fumonisin B1 levels in cereals and feeds from southern Brazil. Arq Inst Biol Sao Paulo 68:41–45Google Scholar
- 4.European Commission (2000) Opinion of the scientific committee of food on fusarium toxins part 3: fumonisin B1 (FB1) http://ec.europa.eu/food/fs/sc/scf/out73_en.pdf
- 5.International Agency for Research on Cancer (2002) Fumonisin B1. In: IARC monographs on the evaluation of carcinogenic risks to humans: some traditional herbal medicines, some mycotoxins, naphthalene and styrene. IARC, Lyon, France, 82: 301–366Google Scholar
- 8.Gaspardo B, Del Zotto S, Torelli E, Cividino SR, Firrao G, Della Riccia G, Stefanon B (2012) A rapid method for detection of fumonisins B1 and B2 in corn meal using fourier transform near infrared (FT-NIR) spectroscopy implemented with integrating sphere. Food Chem 135:1608–1612CrossRefGoogle Scholar
- 10.Shiu CM, Wang JJ, Yu FY (2010) Sensitive enzyme-linked immunosorbent assay and rapid one-step immunochromatographic strip for fumonisin B1 in grain-based food and feed samples. J Sci Food Agric 90:1020–1026Google Scholar
- 33.Azcona-Olivera JI, Abouzied MM, Plattner RD, Norred WP, Pestka JJ (1992) Generation of antibodies reactive with Fumonisin B1, B2 and B3 by using cholera toxin as the carrier-adjuvant. Appl Environ Microbiol 58:169–173Google Scholar