Abstract

Nosocomial infections caused by enterococci are an ongoing global threat. Thus, finding therapeutic agents for the treatment of such infections are crucial. Some Enterococcus faecalis strains are able to produce antimicrobial peptides called bacteriocins. We analyzed 65 E. faecalis isolates from 43 food samples and 22 clinical samples in Egypt for 17 common bacteriocin-encoding genes of Enterococcus spp. These genes were absent in 11 isolates that showed antimicrobial activity putatively due to bacteriocins (three from food, including isolate OS13, and eight from clinical isolates). The food-isolated E. faecalis OS13 produced bacteriocin-like inhibitory substances (BLIS) named enterocin OS13, which comprised two peptides (enterocin OS13α OS13β) that inhibited the growth of antibiotic-resistant nosocomial E. faecalis and E. faecium isolates. The molecular weights of enterocin OS13α and OS13β were determined as 8079 Da and 7859 Da, respectively, and both were heat-labile. Enterocin OS13α was sensitive to proteinase K, while enterocin OS13β was resistant. Characterization of E. faecalis OS13 isolate revealed that it belonged to sequence type 116. It was non-hemolytic, bile salt hydrolase-negative, gelatinase-positive, and sensitive to ampicillin, penicillin, vancomycin, erythromycin, kanamycin, and gentamicin. In conclusion, BLIS as enterocin OS13α and OS13β represent antimicrobial agents with activities against antibiotic-resistant enterococcal isolates.

Details

Title
Purification and characterization of bacteriocins-like inhibitory substances from food isolated Enterococcus faecalis OS13 with activity against nosocomial enterococci
Author
El-Gendy, Ahmed O 1 ; Brede, Dag A 2 ; Essam, Tamer M 3 ; Amin, Magdy A 3 ; Ahmed, Shaban H 4 ; Holo Helge 2 ; Nes, Ingolf F 2 ; Shamikh, Yara I 5 

 Beni-Suef University, Microbiology and Immunology Department, Faculty of Pharmacy, Beni Suef, Egypt (GRID:grid.411662.6) (ISNI:0000 0004 0412 4932) 
 Norwegian University of Life Sciences, Department of Chemistry, Biotechnology and Food Science, Laboratory of Microbial Gene Technology and Food Microbiology, Ås, Norway (GRID:grid.19477.3c) (ISNI:0000 0004 0607 975X) 
 Cairo University, Microbiology and Immunology Department and Biotechnology Centre, Faculty of Pharmacy, Cairo, Egypt (GRID:grid.7776.1) (ISNI:0000 0004 0639 9286) 
 Assiut University, Microbiology and Immunology Department, Faculty of Medicine, Asyût, Egypt (GRID:grid.252487.e) (ISNI:0000 0000 8632 679X) 
 Nahda University, Department of Microbiology and Immunology, Beni Suef, Egypt (GRID:grid.442628.e) (ISNI:0000 0004 0547 6200); Egypt Center for Research and Regenerative Medicine, Department of Virology, Cairo, Egypt (GRID:grid.511464.3) (ISNI:0000 0005 0235 0917) 
Publication year
2021
Publication date
2021
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2607083866
Copyright
© The Author(s) 2021. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.