title: [Genetic diversity of ATP synthase cab subunits amplified from Streptococcus mutans clinical isolates from Uyghur children with different caries susceptibility].
abstract: OBJECTIVE
  To investigate the aciduricity and genetic diversity of ATP synthase subunit gene uncEBF derived from Uyghur children Streptococcus mutans (Sm) clinical isolates and the relationship between the genetic diversity of ATP synthase and Sm aciduric ability and caries susceptibility.
  
  
  METHODS
  Forty-one Sm strains derived from 24 caries-active individuals and 17 caries-free individuals, including 16 strains displaying high acid tolerance and 17 strains displaying low acid tolerance. Solutions of all isolated Sm with same density were made and cultured at pH 4.0 to 7.0 brain heart infusion (BHI) liquid. Terminal growth situation was compared. Gene uncEBF of these isolates were amplified with specific primers from Sm genomic DNA, and the polymerase chain reaction (PCR) products were analyzed by PCR-restriction fragment length polymorphism (RFLP) and sequenced.
  
  
  RESULTS
  Aciduric ability of Sm isolated from the high caries-susceptible children were higher than that isolated from caries-free group (P = 0.023). Alu I digested fragments of uncEBF displayed two different patterns A and B. The distributions of A and B genotype strains with different acidurance were different (P = 0.039). A genotype included 7 strains displaying high acid tolerance and 2 strains displaying low acid tolerance;B genotype included 9 strains displaying high acid tolerance and 15 strains displaying low acid tolerance. The distributions of A and B genotype strains in different caries-sensitivity groups were different (P = 0.009). A genotype included 7 high caries-susceptible strains and 12 caries-free strains; B genotype included 17 high caries-susceptible strains and 5 caries-free strain. Some of these amplified uncEBF genes from different genotype were sequenced and testified that there existed variation of Alu I recognized sites.
  
  
  CONCLUSIONS
  The high cariogenecity of Sm strains isolated from caries-active children shows a close relationship with the high aciduric ability of the isolated Sm strains. uncEBF gene of Sm F-ATPase obviously exhibits genetic diversity.
authors.affiliation: Department of Operative Dentistry and Endodontics, The First Affiliated Hospital, Xinjiang Medical University & Xinjiang Institute of Stomatology, Urumqi 830054, China.
authors.forename: Zhen-hua
authors.initials: ZH
authors.lastname: Liu
authors.forename: Bing-jie
authors.initials: BJ
authors.lastname: Lian
authors.forename: Jin
authors.initials: J
authors.lastname: Zhao
mesh_terms: D025243:Bacterial Proton-Translocating ATPases / Q000235:genetics* / Q000378:metabolism; D002675:Child, Preschool; D002681:China / Q000208:ethnology; D003731:Dental Caries / Q000382:microbiology*; D003733:Dental Caries Susceptibility; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D006863:Hydrogen-Ion Concentration; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D013295:Streptococcus mutans / Q000201:enzymology* / Q000302:isolation & purification
chemical_list: D025243:Bacterial Proton-Translocating ATPases