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High efficiency acetylcholinesterase immobilization on DNA aptamer modified surfaces.

ABSTRACT: We report here the in vitro selection of DNA aptamers for electric eel acetylcholinesterase (AChE). One selected aptamer sequence (R15/19) has a high affinity towards the enzyme (Kd=157±42 pM). Characterization of the aptamer showed its binding is not affected by low ionic strength (~20 mM), however significant reduction in affinity occurred at high ionic strength (~1.2 M). In addition, this aptamer does not inhibit the catalytic activity of AChE that we exploit through immobilization of the DNA on a streptavidin-coated surface. Subsequent immobilization of AChE by the aptamer results in a 4-fold higher catalytic activity when compared to adsorption directly on to plastic.

SUBMITTER: Chumphukam O

PROVIDER: S-EPMC6271157 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature

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High efficiency acetylcholinesterase immobilization on DNA aptamer modified surfaces.

Chumphukam Orada O Le Thao T TT Cass Anthony E G AE

Molecules (Basel, Switzerland) 20140421 4

We report here the in vitro selection of DNA aptamers for electric eel acetylcholinesterase (AChE). One selected aptamer sequence (R15/19) has a high affinity towards the enzyme (Kd=157±42 pM). Characterization of the aptamer showed its binding is not affected by low ionic strength (~20 mM), however significant reduction in affinity occurred at high ionic strength (~1.2 M). In addition, this aptamer does not inhibit the catalytic activity of AChE that we exploit through immobilization of the DNA ...[more]

PMID: 24756130

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