High Level of Biofilm Formation and Virulence Factors in Enterococci Species Isolated From Clinical and Normal Flora Samples. Issue 1 (January 2018)

• Record Type: Journal Article
• Authors: Esmaeili, Zahra; Sadeghi, Javad; Razavi, Shabnam; Oshaghi, Mojgan; Sayyahfar, Shirin; Rahbar, Mohammad; Talebi, Malihe
• Is Part Of: Infectious diseases in clinical practice. Volume 26:Issue 1(2018:Jan.)
• Publication Date: 2018-01
• Subjects: biofilm -- Enterococci -- virulence gene; Communicable diseases -- Periodicals; Communicable Diseases -- Periodicals; Communicable diseases; Periodicals; Periodicals; Electronic journals; 616.9
• DOI: 10.1097/IPC.0000000000000519
• Languages: English
• ISSNs: 1056-9103

Abstract

Abstract : Abstract: Enterococci are gram-positive bacteria, and they are members of normal intestinal microflora of humans as well as animals. However, recently, they evolved from common avirulent commensal bacteria into a multidrug-resistant health care–associated pathogen. In this study, 147 isolates were collected from clinical and healthy people. The presence of 7 genes including ace, ebp, efaA, ebrB, ecbA, fsrB, and sgrA were investigated by polymerase chain reaction method. Finally, for detection of biofilm formation, Congo red agar and microliter plate methods were used. Our results showed that ace (94.6%), efaA (94.6%), and ebp (92.5%) were present almost in all of the isolates, followed by fsrB (53.7%), sgrA (36%), ecbA (33.3%), and ebrB (13.6%). By Congo red method, 38% of our isolates formed black colonies on Congo red agar (biofilm producer), whereas others (62%) had red colonies (nonbiofilm producer). Finally, by using microliter plate method, 23.8% of isolates were able to form biofilm. These results indicate that normal flora isolates can constitute as a reservoir for virulent Enterococcus isolates. Abstract : All normal f lora isolates were identified as Enterococcus faecalis . A high prevalence of virulence genes was identified. All E. faecalis isolates (n = 33, 100%) were positive for the ace and efaA genes while negative for the ebrB gene. Thirty-eight percent of isolates shaped black colonies on Congo red agar; while by the Microtitr Plate method, the rate of biofilm producer was 23%. All strong biofilm formers belonged to clinical samples.