| Autor: |
Truşcă BS; Fundeni Clinical Institute, 022328 Bucharest, Romania.; Department of Microbiology and Immunology, Faculty of Biology, University of Bucharest, 060101 Bucharest, Romania., Gheorghe-Barbu I; Department of Microbiology and Immunology, Faculty of Biology, University of Bucharest, 060101 Bucharest, Romania.; Research Institute of the University of Bucharest-ICUB, 91-95 Spl. Independentei, 050567 Bucharest, Romania., Manea M; Fundeni Clinical Institute, 022328 Bucharest, Romania.; Fundeni Clinical Institute, University of Medicine and Pharmacy 'Carol Davila' Bucharest, 020021 Bucharest, Romania., Ianculescu E; Fundeni Clinical Institute, 022328 Bucharest, Romania., Barbu IC; Department of Microbiology and Immunology, Faculty of Biology, University of Bucharest, 060101 Bucharest, Romania.; Research Institute of the University of Bucharest-ICUB, 91-95 Spl. Independentei, 050567 Bucharest, Romania., Măruțescu LG; Department of Microbiology and Immunology, Faculty of Biology, University of Bucharest, 060101 Bucharest, Romania.; Research Institute of the University of Bucharest-ICUB, 91-95 Spl. Independentei, 050567 Bucharest, Romania., Dițu LM; Department of Microbiology and Immunology, Faculty of Biology, University of Bucharest, 060101 Bucharest, Romania.; Research Institute of the University of Bucharest-ICUB, 91-95 Spl. Independentei, 050567 Bucharest, Romania., Chifiriuc MC; Department of Microbiology and Immunology, Faculty of Biology, University of Bucharest, 060101 Bucharest, Romania.; Research Institute of the University of Bucharest-ICUB, 91-95 Spl. Independentei, 050567 Bucharest, Romania.; Romanian Academy, 050045 Bucharest, Romania., Lazăr V; Department of Microbiology and Immunology, Faculty of Biology, University of Bucharest, 060101 Bucharest, Romania. |
| Abstrakt: |
A current major healthcare problem is represented by antibiotic resistance, mainly due to multidrug resistant (MDR) Gram negative bacilli (GNB), because of their extended spread both in hospital facilities and in the community's environment. The aim of this study was to investigate the virulence traits of Klebsiella pneumoniae , Acinetobacter baumannii, and Pseudomonas aeruginosa MDR, XDR, and PDR strains isolated from various hospitalized patients. These GNB strains were investigated for the presence of soluble virulence factors (VF), such as hemolysins, lecithinase, amylase, lipase, caseinase, gelatinase, and esculin hydrolysis, as well as for the presence of virulence genes encoding for VF involved in adherence ( TC , fimH , and fimA ), biofilm formation ( algD , ecpRAB , mrkA , mrkD , ompA , and epsA ), tissue destruction ( plcH and plcN ), and in toxin production ( cnfI , hlyA , hlyD , and exo complex). All P. aeruginosa strains produced hemolysins; 90% produced lecithinase; and 80% harbored algD, plcH, and plcN genes. The esculin hydrolysis was detected in 96.1% of the K. pneumoniae strains, whereas 86% of them were positive for the mrkA gene. All of the A. baumannii strains produced lecithinase and 80% presented the ompA gene. A significant association was found between the number of VF and the XDR strains, regardless of the isolation sources. This study opens new research perspectives related to bacterial fitness and pathogenicity, and it provides new insights regarding the connection between biofilm formation, other virulence factors, and antibiotic resistance. |
