الفهرس | Only 14 pages are availabe for public view |
Abstract Enterococci are widely distributed bacteria that are incriminated in various clinical conditions in humans and economic losses in fish farms. The aim of this study was to recognize Enterococcus sp. and their virulence from diseased Nile tilapia and humans, and assess the accuracy of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) in recognizing Enterococcus species. Septicemic farmed O. niloticus (n=70) and human blood, urine, and pus samples (n=45), were collected from Sharkia Governorate and Suez Canal University Hospital, Ismailia, Egypt, respectively. Samples were tested bacteriologically and molecularly for identification of Enterococcus sp.; moreover, carriage of virulence genes by the isolates had been evaluated. Proteomic (MALDI-TOF MS) was also used to assess its ability to identify Enterococcus sp. in comparison to conventional PCR technique. Overall, Enterococcus sp. was identified in Nile tilapia (32.9%) and human samples (28.9%). Two species of enterococci; E. faecalis and E. faecium, were identified with E. faecalis was the most prevalent species in both fish and human samples. High occurrence of four virulence genes (gelE) (86.1%), (cylA) (86.1%), (asa1) (77.8%), (esp) (72.2%) had been detected in Enterococcus sp. isolates, however, (hyl) (19.4%) was the lowest. Using MALDI-TOF MS, five of ten examined isolates were identified as Enterococcus sp., however, all isolates were confirmed to be Enterococcus using conventional PCR. The study confirmed that PCR is the most accurate method for identification of Enterococcus sp. and using MALDI-TOF MS as the only identification method is not advisable. |