Monospecies and mixed biofilms of Trichophyton and Staphylococcus: influence of nutrients and presence of persister cells

• Grant number: 21/03805-6
• Support Opportunities: Scholarships in Brazil - Master
• Start date: October 01, 2021
• End date: April 30, 2023
• Field of knowledge: Health Sciences - Pharmacy
• Principal Investigator: Maria José Soares Mendes Giannini
• Grantee: Jenyffie Araujo Belizario
• Host Institution: Faculdade de Ciências Farmacêuticas (FCFAR). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

Dermatophytes are fungi that infect keratinized tissues such as skin, hair, and nails, causing dermatophytosis. There is an association between these fungi' lesions with bacteria, in some cases, making treatment more difficult in some cases. Such infections have a high global incidence and are of great interest to public health. Although some of these fungi can form monospecies biofilms, their association with the skin microbiota's commensal organisms such as Staphylococcus epidermidis or nosocomial microorganisms such as Staphylococcus aureus in biofilm formation is not elucidated. Resistance in biofilms is multifactorial and may be associated with so-called persister cells. Besides, environmental factors such as the availability of nutrients provided by the biofilm environment influence the adhesion capacity and biofilm architecture. Thus, in this study, the ability to form a mixed biofilm of dermatophytes from the genus Trichophyton (T. rubrum) with S. aureus and S. epidermidis will be evaluated in different culture media and at different times of biofilm formation. In addition, persisters cells will be quantified after exposure of biofilms to antimicrobials. The biofilm formation capacity of dermatophytes in monospecies or mixed biofilms will be evaluated in 96-well microtiter plates and quantified by counting colony-forming units on agar and the violet crystal methodology. The biofilms' topography will be shown with scanning electron microscopy and confocal laser scanning microscopy (CLSM). The quantification of persister cells will be performed by plating on agar after exposure of the biofilms to vancomycin or terbinafine, statistically comparing the quantities obtained in monospecies or mixed biofilms. The knowledge of the interactions between microorganisms that make up mixed biofilms is relevant to the host's immune response, resistance to antimicrobials, and disease progression, since persistent cells may be the main reason for chronic infectious disease recalcitrance, so this study may be a subsidy for future therapeutic studies involving antibiofilm treatment, also considering its possible persistent fraction. (AU)

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)

FUSCO-ALMEIDA, ANA MARISA; SILVA, SAMANTA DE MATOS; DOS SANTOS, KELVIN SOUSA; GUALQUE, MARCOS WILLIAM DE LIMA; VASO, CAROLINA ORLANDO; CARVALHO, ANGELICA ROMAO; MEDINA-ALARCON, KAILA PETROLINA; PIRES, ANA CAROLINA MOREIRA DA SILVA; BELIZARIO, JENYFFIE ARAUJO; DE SOUZA FERNANDES, LIGIA; et al. Alternative Non-Mammalian Animal and Cellular Methods for the Study of Host-Fungal Interactions. JOURNAL OF FUNGI, v. 9, n. 9, p. 29-pg., 2023-09-01. (20/15586-4, 21/14839-9, 21/03805-6, 19/23622-3)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

BELIZARIO, Jenyffie Araujo. Monoespecies and mixed biofilms of Trichophyton and Staphylococcus: nutrient influence and presence of persisters cells. 2023. Master's Dissertation - Universidade Estadual Paulista (Unesp). Faculdade de Ciências Farmacêuticas. Araraquara Araraquara.