Burkholderia contaminans in cystic fibrosis: genetic and phenotypic diversity among isolates from long-term infections

A. BOSCH,; P. MARTINA, ; C. PRIETO,; B. VALEIRAS,; M. BETTIOL, ; P. MONTANARO, ; O. YANTORNO

GOTHENBURG, SWEDEN

Congreso; 37th EUROPEAN CYSTIC FIBROSIS CONFERENCE; 2014

European Cystic Fibrosis Society

Aim: The aim of the present w ork w as to get insights into the genetic and phenotypic diversity of B. contaminans clinical isolates recovered from long-term infection in cystic fibrosis (CF) patients Methods: A total of 65 B. contaminans isolates recovered from serial sputum cultures from 13 chronically infected patients attended at 3 CF treatment centers in Argentina during a 10-year period (2004-2013) w as analyzed. Isolates w ere identified by recA-PCR sequencing and recA-RFLP-HaeIII restriction analysis, and genotyping by BOX-PCR fingerprinting. Phenotypic diversity among the isolates w as analyzed, by colony morphology, grow th rate, production of haemolysin, lipases and proteases expression, EPS and biofilm formation, antibiotic resistance and by Fourier transform infrared (FT-IR) spectroscopy. Results: The w hole B. contaminans population 11 displayed different BOX subtypes . Nine BOXsubtypes w ere found during the first year of infection for the different patients. Nevertheless, the genotypic diversity of the isolates decreased for all the isolates retrieved from chronically infected patients, w here only 2 Box subtypes could be determined. In contrast to this genotyping diversity evolution, a high phenotypic diversity -w ith a decrease expression of the virulence factorscharacterized the isolates recovered both from different patients and from each patient along the chronic infections. Conclusion: Our results revealed evidences of genetic and phenotypic adaptation of B. contaminans isolates during chronic lung infections that could contribute to increase the capacity of these bacteria to survive and persist in their host