title: Capillary electrophoresis-SELEX selection of catalytic DNA aptamers for a small-molecule porphyrin target.
abstract: Capillary electrophoresis-systematic evolution of ligands by exponential enrichment (CE-SELEX) has previously been used to select aptamers for large-molecule targets such as proteins, lipopolysaccharides, and peptides. For the first time, we have performed CE-SELEX selection for a small-molecule target, N-methyl mesoporphyrin (NMM), with a molecular weight of only 580 g/mol. DNA aptamers with high-nanomolar to low-micromolar dissociation constants were achieved after only three rounds of selection. This corresponds to an >50-fold improvement in affinity over the random library. Two out of eight randomly chosen aptamers were found to catalyze the metal insertion reaction of mesoporphyrin with 1.7- and 2.0-fold rate enhancements, respectively.
authors.affiliation: Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States.
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.forename: Michael T
authors.initials: MT
authors.lastname: Bowser
mesh_terms: D052157:Aptamers, Nucleotide / Q000235:genetics / Q000378:metabolism*; D020134:Catalytic Domain / Q000502:physiology*; D019075:Electrophoresis, Capillary / Q000379:methods; D018390:Gene Targeting / Q000379:methods*; D011166:Porphyrins / Q000235:genetics / Q000378:metabolism*; D011897:Random Allocation; D052156:SELEX Aptamer Technique / Q000379:methods*
chemical_list: D052157:Aptamers, Nucleotide; D011166:Porphyrins