Interações de isolados clínicos de Prevotella intermedia e Prevotella nigrescens com Porphyromonas gingivalis na formação de biofilmes

Autor: Graziela Murta Barbosa
Přispěvatelé: Maria Regina Lorenzetti Simionato, Paulo Henrique Rodrigues, Marina Clemente Conde, Antonio Olavo Cardoso Jorge, Ericka Tavares Pinheiro, Luciana Saraiva
Jazyk: portugalština
Rok vydání: 2013
Předmět:
Zdroj: Biblioteca Digital de Teses e Dissertações da USP
Universidade de São Paulo (USP)
instacron:USP
Popis: Barbosa GM. Interactions of clinical isolates of Prevotella intermedia and Prevotella revotella intermedia and Prevotella nigrescens are commonly associated with periodontal nigrescens with Porphyromonas gingivalis in biofilms formation. [Ph. D. thesis (Microbiology)]. Sao Paulo: Instituto de Ciencias Biomedicas, Universidade de Sao Paulo; 2013. P diseases. In the oral cavity both species are frequently detected in biofilms associated with other periodontal pathogens, such as Porphyromonas gingivalis. Few studies have investigated biofilm formation of P. intermedia and P. nigrescens and their association with other periodontal pathogens. Thus, the goals of this study were to determine the coaggregation of strains of P. intermedia, P. nigrescens and P. gingivalis; to quantify the biomass of these associations, to evaluate the ratio of these microorganisms in heterotypic biofilms, to verify the modulation of biofilms in co-culture using a trans-well system; to evaluate the structure of the biofilms by Fluorescent Hybridization In Situ (FISH) and to determine the role of genes PINA0102 and PIN0398 of P. intermedia in the modulation of its biofilm. Therefore, nine clinical isolates of P. intermedia, five of P. nigrescens, type strains P. intermedia 17, P. intermedia 25611, P. nigrescens 33563, P. gingivalis W83, P. gingivalis 33277 and mutant strains Pi17∆PIN0398 and Pi17∆PINA0102 were grown in consortia of two strains. It was determined that the consortium P. intermedia 17 and P. gingivalis 33277 had the highest co-aggregation and the consortia of P. nigrescens 33563 with both strains of P. gingivalis had the lowest. Despite of P. intermedia 25611 produce the highest biomass in homotypic biofilm, the highest biomass in heterotypic biofilms has been verified for the consortium P. intermedia 17 and P. gingivalis W83. It was also determined that heterotypic biofilms of P. nigrescens 33563 with both strains of P. gingivalis had higher biomass than the respective homotypic biofilm of each strain. The biomasses of all associations of clinical isolates of P. intermedia with P. gingivalis W83 fluctuated when compared to each respective homotypic biofilm. When the clinical isolates were associated with P. gingivalis ATCC, most associations had an increased biomass which may demonstrate a strain-specific interaction. It also has been shown that most of the associations of clinical isolates of P. intermedia with P. nigrescens ATCC had an increase in biomass when compared to each respective homotypic biofilm. While a fluctuate biomass was verified in the consortia of clinical isolates of P. nigrescens with both type strains of P. intermedia, an increased biomass was verified for all associations of clinical isolates of P. nigrescens with both type strains of P. gingivalis. In addition, the ratio data of each strain in heterotypic biofilms have shown a higher mass of P. gingivalis in all consortia with P. intermedia strains except in the consortium of P. intermedia 17 and P. gingivalis W83. For the associations of P. intermedia with P. nigrescens ATCC a fluctuate ratio data have been determined, while a higher mass of both type strains of P. gingivalis has been determined in the consortia with P. nigrescens. In the two-compartment separated co-culture system P. intermedia had an increased biomass when co-cultured with P. gingivalis while only P. gingivalis ATCC had an increased biomass in this system. It was confirmed the biomass data of the type strains by the FISH assays. Genes PINA0102 and PIN0398 do modulate biofilm of P. intermedia regarding biomass, ratio in a heterotypic biofilm and in a co-culture system with type strains of P. gingivalis and P. nigrescens. Our data demonstrate that the associations of P. intermedia, P. nigrescens and P. gingivalis are strain-specific and further investigations are necessary to elucidate the mechanism (s) involved in the interactions between these species.
Databáze: OpenAIRE