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By-product formation in repetitive PCR amplification of DNA libraries during SELEX.

ABSTRACT: The selection of nucleic acid aptamers is an increasingly important approach to generate specific ligands binding to virtually any molecule of choice. However, selection-inherent amplification procedures are prone to artificial by-product formation that prohibits the enrichment of target-recognizing aptamers. Little is known about the formation of such by-products when employing nucleic acid libraries as templates. We report on the formation of two different forms of by-products, named ladder- and non-ladder-type observed during repetitive amplification in the course of in vitro selection experiments. Based on sequence information and the amplification behaviour of defined enriched nucleic acid molecules we suppose a molecular mechanism through which these amplification by-products are built. Better understanding of these mechanisms might help to find solutions minimizing by-product formation and improving the success rate of aptamer selection.

SUBMITTER: Tolle F

PROVIDER: S-EPMC4260880 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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By-product formation in repetitive PCR amplification of DNA libraries during SELEX.

Tolle Fabian F Wilke Julian J Wengel Jesper J Mayer Günter G

PloS one 20141209 12

The selection of nucleic acid aptamers is an increasingly important approach to generate specific ligands binding to virtually any molecule of choice. However, selection-inherent amplification procedures are prone to artificial by-product formation that prohibits the enrichment of target-recognizing aptamers. Little is known about the formation of such by-products when employing nucleic acid libraries as templates. We report on the formation of two different forms of by-products, named ladder- a ...[more]

PMID: 25490402

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