title: [Selection and identification of ssDNA aptamers specific to clinical isolates of Streptococcus mutans strains with different cariogenicity].
abstract: OBJECTIVE
  To select and identify ssDNA aptamers specific to Streptococcus mutans strains with different cariogenicity isolated from clinical specimens.
  
  
  METHODS
  Subtractive SELEX technology targeting the whole intact cells was used to screen for ssDNA aptamers specific to the clinical isolates Streptococcus mutans strains with different cariogenicity. Radioactive isotope, flow cytometry, gene cloning and sequencing, MEME online software and RNA structure analysis software were employed to analyze the first and secondary structures of the aptamers and identify the screened aptamers.
  
  
  RESULTS
  Detection by radioactive isotope showed sufficient pool enrichment after 9 rounds of subtractive SELEX. Flow cytometry showed that the selected aptamers H1, H16, H4, L1, L10 and H19 were capable of binding specifically with highly cariogenic Streptococcus mutans strains but not with strains with a low cariogenicity. The aptamer H19 had the strongest binding capacity to highly cariogenic Streptococcus mutans strains, with a dissociation constant of 69.45∓38.53 nmol/L.
  
  
  CONCLUSIONS
  We have obtained the ssDNA aptamers specific to the clinical isolates of highly cariogenic Streptococcus mutans strains.
authors.affiliation: Department of Stomatology, General Hospital of PLA, Beijing, China. wangchenglong9@hotmail.com
authors.forename: Chenglong
authors.initials: C
authors.lastname: Wang
authors.forename: Danyang
authors.initials: D
authors.lastname: Hu
authors.forename: Jiaojiao
authors.initials: J
authors.lastname: Liu
authors.forename: Shaohua
authors.initials: S
authors.lastname: Li
authors.forename: Donghua
authors.initials: D
authors.lastname: Su
authors.forename: Qing
authors.initials: Q
authors.lastname: Xi
authors.forename: Bingfeng
authors.initials: B
authors.lastname: Chu
authors.forename: Wei
authors.initials: W
authors.lastname: Xia
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhao
authors.forename: Hongmei
authors.initials: H
authors.lastname: Ding
authors.forename: Yanping
authors.initials: Y
authors.lastname: Luo
authors.forename: Jiyong
authors.initials: J
authors.lastname: Yang
authors.forename: Bin
authors.initials: B
authors.lastname: Deng
authors.forename: Juan
authors.initials: J
authors.lastname: Xu
authors.forename: Ningsheng
authors.initials: N
authors.lastname: Shao
mesh_terms: D052157:Aptamers, Nucleotide / Q000235:genetics*; D003001:Cloning, Molecular; D017931:DNA Primers; D003731:Dental Caries / Q000382:microbiology; D015723:Gene Library; D006801:Humans; D009690:Nucleic Acid Conformation; D052156:SELEX Aptamer Technique; D013045:Species Specificity; D013295:Streptococcus mutans / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*
chemical_list: D052157:Aptamers, Nucleotide; D017931:DNA Primers