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Selection, Characterization and Application of Artificial DNA Aptamer Containing Appended Bases with Sub-nanomolar Affinity for a Salivary Biomarker.

ABSTRACT: We have attained a chemically modified DNA aptamer against salivary ?-amylase (sAA), which attracts researchers' attention as a useful biomarker for assessing human psychobiological and social behavioural processes, although high affinity aptamers have not been isolated from a random natural DNA library to date. For the selection, we used the base-appended base (BAB) modification, that is, a modified-base DNA library containing (E)-5-(2-(N-(2-(N6-adeninyl)ethyl))carbamylvinyl)-uracil in place of thymine. After eight rounds of selection, a 75 mer aptamer, AMYm1, which binds to sAA with extremely high affinity (K_d?

SUBMITTER: Minagawa H

PROVIDER: S-EPMC5335659 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Selection, Characterization and Application of Artificial DNA Aptamer Containing Appended Bases with Sub-nanomolar Affinity for a Salivary Biomarker.

Minagawa Hirotaka H Onodera Kentaro K Fujita Hiroto H Sakamoto Taiichi T Akitomi Joe J Kaneko Naoto N Shiratori Ikuo I Kuwahara Masayasu M Horii Katsunori K Waga Iwao I

Scientific reports 20170303

We have attained a chemically modified DNA aptamer against salivary α-amylase (sAA), which attracts researchers' attention as a useful biomarker for assessing human psychobiological and social behavioural processes, although high affinity aptamers have not been isolated from a random natural DNA library to date. For the selection, we used the base-appended base (BAB) modification, that is, a modified-base DNA library containing (E)-5-(2-(N-(2-(N6-adeninyl)ethyl))carbamylvinyl)-uracil in place of ...[more]

PMID: 28256555

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