title: On the use of denaturing gradient gel electrophoresis approach for bacterial identification in endodontic infections.
abstract: Bacteria in infected root canals of teeth evincing chronic apical periodontitis lesions were identified by a polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) approach. DNA was extracted from root canal samples, and part of the 16S rRNA gene of all bacteria was amplified by PCR and separated by DGGE, generating banding patterns representative of the community structure. Twenty visible bands were cut out of the gel, re-amplified, and sequenced to provide identification. Sequencing analysis revealed the presence of both cultivable and as-yet-uncultivated species in the samples analyzed, including representatives of the genera Fusobacterium, Bacteroides, Dialister, Synergistes, Prevotella, Eubacterium and Peptostreptococcus. Unambiguous identification was not always possible and the method's limitations are discussed. In general, the findings showed that PCR-DGGE can be useful for the identification of both cultivable and as-yet-uncultivated bacteria in endodontic infections.
authors.affiliation: Universidade Estácio de Sá, Av. Paulo de Frontin 628, 5 andar, Rio de Janeiro 20261-243, Brazil.
authors.forename: Julio C
authors.initials: JC
authors.lastname: Machado de Oliveira
authors.forename: Tulio G V
authors.initials: TG
authors.lastname: Gama
authors.forename: José F
authors.initials: JF
authors.lastname: Siqueira
authors.forename: Isabela N
authors.initials: IN
authors.lastname: Rôças
authors.forename: Raquel S
authors.initials: RS
authors.lastname: Peixoto
authors.forename: Alexandre S
authors.initials: AS
authors.lastname: Rosado
mesh_terms: D000328:Adult; D001421:Bacteria, Anaerobic / Q000235:genetics; D001424:Bacterial Infections / Q000382:microbiology*; D015373:Bacterial Typing Techniques; D002908:Chronic Disease; D004269:DNA, Bacterial / Q000032:analysis; D003786:Dental Pulp Cavity / Q000382:microbiology*; D003790:Dental Pulp Necrosis / Q000382:microbiology; D004587:Electrophoresis, Agar Gel / Q000379:methods*; D006801:Humans; D010485:Periapical Periodontitis / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S