title: Differential Proteinase Patterns among Candida albicans Strains Isolated from Root Canal and Lingual Dorsum: Possible Roles in Periapical Disease.
abstract: BACKGROUND
  Proteinases play pivotal roles in Candida albicans infections. Although the yeast can colonize the pulpal environment, there is no information about the enzymatic profile of this organism. This in vitro study aimed to determine the proteolysis levels and to investigate differences in the expression of aspartyl proteinase genes (Sap 1, Sap 2, and Sap 4) among various root canal strains and clinical isolates from the lingual dorsum.
  
  
  METHODS
  The extracellular proteinase activity of 104 C. albicans samples isolated from the lingual dorsum and from necrotic root canals was measured with respect to bovine serum albumin degradation after 5 days of incubation at 37°C. We used reverse-transcription polymerase chain reaction, a highly sensitive method, to detect messenger RNA transcripts of aspartyl proteinase genes (Sap 1, Sap 2, and Sap 4). The C. albicans strain SC 5314 was used as a positive control for both experiments because it is recognized as being highly proteolytic. All tests were performed in triplicate.
  
  
  RESULTS
  Regardless of the isolation site, all C. albicans strains produced an opaque precipitation halo around the colonies, indicating some proteinase activity. However, the production of proteinase on the plates was significantly greater (P < .05) by the endodontic samples. Sap 2 was the most commonly expressed gene in all samples. Among the root canal samples, the detection of Sap 1 transcripts was always associated with the expression of Sap 2 and Sap 4. Sap 4 gene expression was detected in all root canal samples. The simultaneous expression of the 3 investigated Sap genes (Sap 1, Sap 2, and Sap 4) was more common in strains isolated from the lingual dorsum (50%) than in those isolated from root canals (29.4%).
  
  
  CONCLUSIONS
  The increased proteolytic activity as well as the distinct pattern of Sap expression observed among the root canal samples may suggest a pathogenic role for C. albicans in endodontic infections.
authors.affiliation: Department of Microbiology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. Electronic address: microtati@yahoo.com.br.
authors.forename: Tatiana Teixeira
authors.initials: TT
authors.lastname: Miranda
authors.affiliation: Department of General Education, Federal Center of Technological Education, Varginha, Minas Gerais, Brazil.
authors.forename: Cristina R
authors.initials: CR
authors.lastname: Vianna
authors.affiliation: Department of Microbiology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Rodrigues
authors.affiliation: Department of Microbiology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Carlos Augusto
authors.initials: CA
authors.lastname: Rosa
authors.affiliation: Department of Microbiology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Ary
authors.initials: A
authors.lastname: Corrêa
mesh_terms: D057055:Aspartic Acid Proteases / Q000235:genetics / Q000378:metabolism*; D002176:Candida albicans / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D003786:Dental Pulp Cavity / Q000201:enzymology / Q000382:microbiology*; D015870:Gene Expression; D006801:Humans; D010483:Periapical Diseases / Q000201:enzymology / Q000382:microbiology*
chemical_list: D057055:Aspartic Acid Proteases
keywords: Aspartyl proteinases; Candida albicans; root canal; virulence factors