Proteomic profile of bacteria present in root canals of teeth with symptomatic or asymptomatic apical periodontitis.

Author(s)

Felipe Ricardo Nunes de Moraes

• Document type: Master's Dissertation
• Press: Araçatuba. 2021-05-19.
• Institution: Universidade Estadual Paulista (Unesp). Faculdade de Odontologia. Araçatuba
• Defense date: 2020-10-28
• Advisor: Rogério de Castilho Jacinto

Abstract

Endodontic infections are caused by a multispecies community of bacteria. With microbiological identification methods and endotoxin quantification, it is difficult to infer physiology, function and microbial pathogenicity. Thus, proteomic analysis is a technique that can revolutionize the study of the pathogenesis of endodontic infections. The present study aims to analyze the proteomic profile of endodontic infections related to teeth with symptomatic or asymptomatic apical periodontitis using liquid chromatography associated with mass spectrometry. The analysis of this proteomic profile aims to provide an understanding of the ecological and pathogenic aspects of the behavior of endodontic bacterial communities by identifying proteins expressed in the said environment at the time of collection and determining the function of these proteins. Samples were collected from 18 patients referred for root canal treatment or emergency treatment at the School of Dentistry of Araçatuba FOA - UNESP. Teeth with primary endodontic infection, symptomatic or asymptomatic were included. The identification of peptides was made in a nanoACQUITY UPLC-Xevo QTof MS system (Waters) system, the identification of proteins was obtained using protein lynx global server (PLGS) software version 3.0, using the UniProtKB protein database. The difference in expression between the groups was obtained through the same software, considering p<0.05 for subregulated proteins and 1-p>0.95 for the superregulated proteins. A total of 2,181 access numbers were identified between human fragments, isoforms and complete proteins and 51 bacterial proteins, and both were classified as their biological function, in relation to the exclusive proteins of each group, 347 proteins were identified in the symptomatic group. The most prevalent biological functions were cellular communication and signal transduction, followed by the immune response, and several proteins were observed exclusively expressed in the symptomatic group, indicating the direct influence of symptomatic periodontitis on the host response. (AU)

• FAPESP's process: 18/08282-9 - Proteomic profile of bacteria present in root canals of teeth with symptomatic or asymptomatic apical periodontitis
• Grantee: Felipe Ricardo Nunes de Moraes
• Support Opportunities: Scholarships in Brazil - Master