Polymicrobial biofilms: study, characterization, evaluation of pathogenicity in Galleria mellonella, and influence in the expression of C. albicans virulence genes.

• Grant number: 13/07411-6
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Effective date (Start): November 01, 2013
• Effective date (End): October 31, 2016
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Antonio Olavo Cardoso Jorge
• Grantee: Cristiane Aparecida Pereira
• Host Institution: Instituto de Ciência e Tecnologia (ICT). Universidade Estadual Paulista (UNESP). Campus de São José dos Campos. São José dos Campos , SP, Brazil

Abstract

Although the number of research with biofilms has increased, less is known about the behavior of mixed microbial communities, particularly interactions between fungi and bacteria. To understand the infectious diseases process and develop new drugs and therapeutic strategies, it is necessary in vitro and in vivo models of polymicrobial biofilms. The study will characterize the polymicrobial biofilms, in vitro, formed by Candida albicans, S. aureus, S. epidermidis and P. aeruginosa; assess pathogenicity of the interaction among these microorganisms in the experimental model of invertebrate Galleria mellonella and expression of virulence genes by C. albicans. This study will be divided in five stages. In stage A, the polymicrobial biofilms will be studied and characterized by the following tests: quantification of viable cells and detached cells from the biofilm metabolic activity by the colorimetric XTT assay, analysis of biomass (dry weight), and assay of bacteria adhered to hyphae. In stage B, biofilms will be analyzed microscopically by scanning electron microscopy and confocal laser scanning microscopy. The effects of enzyme lyticase in the integrity of polymicrobial biofilms will be performed in stage C. In vivo study of microbial pathogenicity in experimental model of G. mellonella will be performed in stage D, through the survival curve of this larva and quantification of micro-organisms. The influence of polymicrobial biofilms in the expression of virulence genes by C. albicans will be evaluated in stage E. Statistical analysis of the results obtained in this study will be performed using Minitab software, considering difference statistically significant when p value is less than 0.05.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

PEREIRA, CRISTIANE APARECIDA; DOMINGUES, NADIA; SANTOS ALVES ARAUJO, MARIA IZABEL DANIEL; JUNQUEIRA, JULIANA CAMPOS; BACK-BRITO, GRAZIELLA NUERNBERG; CARDOSO JORGE, ANTONIO OLAVO. Production of virulence factors in Candida strains isolated from patients with denture stomatitis and control individuals. DIAGNOSTIC MICROBIOLOGY AND INFECTIOUS DISEASE, v. 85, n. 1, p. 66-72, MAY 2016. (10/00879-4, 13/07411-6, 10/08936-7)

PEREIRA, CRISTIANE APARECIDA; DOMINGUES, NADIA; SILVA, MICHELLE PENELUPPI; BORGES PEREIRA COSTA, ANNA CAROLINA; JUNQUEIRA, JULIANA CAMPOS; CARDOSO JORGE, ANTONIO OLAVO. Photodynamic inactivation of virulence factors of Candida strains isolated from patients with denture stomatitis. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY, v. 153, p. 82-89, DEC 2015. (10/00879-4, 11/21346-7, 13/07411-6, 10/08936-7)

DO ROSARIO PALMA, ANA LUIZA; DE PAULA-RAMOS, LUCAS; DOMINGUES, NADIA; BACK-BRITO, GRAZIELLA NUERNBERG; DE OLIVEIRA, LUCIANE DIAS; PEREIRA, CRISTIANE APARECIDA; CARDOSO JORGE, ANTONIO OLAVO. Biofilms of Candida albicans and Streptococcus sanguinis and their susceptibility to antimicrobial effects of photodynamic inactivation. Photodiagnosis and Photodynamic Therapy, v. 24, p. 95-101, DEC 2018. (13/07411-6)