Gene expression and phenotypic traits of Aggregatibacter actinomycetemcomitans in response to environmental changes

Autor(es)

Longo, P. L. ^[1] ; Nunes, A. C. R. ^[1] ; Umeda, J. E. ^[1] ; Mayer, M. P. A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Ciencias Biomed, Dept Microbiol, BR-05508900 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF PERIODONTAL RESEARCH; v. 48, n. 6, p. 766-772, DEC 2013.
• Citações Web of Science: 6

Resumo

Background and ObjectivePeriodontopathogens experience several challenges in the oral cavity that may influence their transcription profile and resulting phenotype. This study evaluated the effect of environmental changes on phenotype and gene expression in a serotype b Aggregatibacter actinomycetemcomitans isolate. Material and MethodsCultures in early exponential phase and at the start of stationary growth phase in microaerophilic and anaerobic atmospheres were evaluated. Cell hydrophobic properties were measured by adherence to n-hexadecane; in addition, adhesion to, and the ability to invade, KB cells was evaluated. Relative transcription of 12 virulence-associated genes was determined by real-time reverse transcritption quantitative PCR. ResultsThe culture conditions tested in this study were found to influence the phenotypic and genotypic traits of A.actinomycetemcomitans. Cells cultured in microaerophilic conditions were the most hydrophobic, reached the highest adhesion efficiency and showed up-regulation of omp100 (which encodes an adhesion) and pga (related to polysaccharide synthesis). Cells grown anaerobically were more invasive to epithelial cells and showed up-regulation of genes involved in host-cell invasion or apoptosis induction (such as apaH, omp29, cagE and cdtB) and in adhesion to extracellular matrix protein (emaA). ConclusionEnvironmental conditions of different oral habitats may influence the expression of factors involved in the binding of A.actinomycetemcomitans to host tissues and the damage resulting thereby, and thus should be considered in in-vitro studies assessing its pathogenic potential. (AU)

• Processo FAPESP: 03/08598-0 - Fatores de virulência de A. actinomycetemcomitans: participação na doença, regulação da expressão, diversidade e resposta imune
• Beneficiário: Marcia Pinto Alves Mayer
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 03/01192-9 - Análise da expressão gênica mediada pelo operon ARC em Actinobacillus actinomycetemcomitans
• Beneficiário: Priscila Larcher Longo
• Modalidade de apoio: Bolsas no Brasil - Doutorado