Classical and molecular epidemiology of Pseudomonas aeruginosa isolated from patients with Cystic Fibrosis

• Grant number: 13/13358-0
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Effective date (Start): November 01, 2013
• Effective date (End): August 31, 2016
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Ana Lúcia da Costa Darini
• Grantee: Natália Candido Caçador
• Host Institution: Faculdade de Ciências Farmacêuticas de Ribeirão Preto (FCFRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated scholarship(s): 14/19310-2 - Mutation, biofilm growth and phenotypic characteristics of Pseudomonas aeruginosa isolated from patients with cystic fibrosis, BE.EP.DD

Abstract

Pseudomonas aeruginosa is the major gram-negative bacterium associated with lung infections in Cystic Fibrosis (CF) patients, which contributes to the increased morbidity and mortality of such disease. P. aeruginosa has the ability to cause progressive damage to patients, mainly because of three factors: hypermutator phenotype; expression of virulence factors; and a remarkable and intrinsic resistance to antibiotics, associated with the ability to acquire new resistance determinants. In Brazil there are few studies related with bacteria isolated from CF patients, restricting the researches to few reference centers of FC. Within this context, the aim of this project is to evaluate strains of P. aeruginosa in CF patients treated at the Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto - Universidade de São Paulo (HCFMRP-USP), and relate all the main features of P. aeruginosa for obtaining of a complete overview of the isolates, namely: virulence factors, antimicrobial susceptibility of clinical-microbiological interest, genomic similarity and occurrence of hypermutable strains. Particularly, phenotypic and molecular methods will be used for: isolation and identification of P. aeruginosa, determination of antibiotic resistance and investigation of the occurrence of virulence factors. The occurrence of hypermutable strains will be determined by a modified disk diffusion method and the mutation frequency will be estimated from the rifampicin resistance displayed by the isolates. Sequencing assays will be realized for detection of: (i) mutations in genes belonging to the system that prevent or repair the mutations in the bacterial DNA; and (ii) mutations in the quorum sensing system genes and in the alginate production gene. The genetic variability of the isolates will be characterized considering the macrorestriction by pulsed-field gel electrophoresis. The isolates will be characterized as mucoid or non-mucoid according to colonial morphology displayed on the first culture, and determination/evaluation of patients with chronic and intermittent colonization will be held in conjunction with the medical team, with the aid of the results obtained by the techniques already described. It is expected that the results of this project contribute to a greater understanding of colonization/infection by P. aeruginosa and that they also play a role in the improvement of the quality of life of CF patients. (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)

CACADOR, NATALIA CANDIDO; DA COSTA CAPIZZANI, CAROLINA PAULINO; MONTEIRO MARIN TORRES, LFDIA ALICE GOMES; GALETTI, RENATA; CIOFU, OANA; DA COSTA DARINI, ANA LTICIA; FLEFIBY, NIELS. Adaptation of Pseudomonas aeruginosa to the chronic phenotype by mutations in the algTmucABD operon in isolates from Brazilian cystic fibrosis patients. PLoS One, v. 13, n. 11, NOV 29 2018. (13/13455-6, 15/11728-0, 14/14494-8, 13/13358-0)

DA COSTA CAPIZZANI, C. P.; CACADOR, N. C.; TORRES, L. A. G. M. M.; TONANI, L.; VANDAMME, P.; DA COSTA DARINI, A. L.. Clinical and microbiological profile of chronic Burkholderia cepacia complex infections in a cystic fibrosis reference hospital in Brazil. EUROPEAN JOURNAL OF CLINICAL MICROBIOLOGY & INFECTIOUS DISEASES, v. 36, n. 11, p. 2263-2271, NOV 2017. (13/13455-6, 13/13358-0, 14/14494-8)

Academic Publications

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

CAÇADOR, Natália Candido. Molecular epidemiology and adaptive genetic characteristics of Pseudomonas aeruginosa related to chronic infection in patients with Cystic Fibrosis and their correlation with clinical data. 2016. Doctoral Thesis - Universidade de São Paulo (USP). Faculdade de Ciências Farmacêuticas de Ribeirão Preto (PCARP/BC) Ribeirão Preto.