Molecular and Bacteriological Study of Enterococcus faecalis Isolated from Different Clinical Sources

  • Khalil H. Khdir Department of Biology, College of Education, Salahaddin University-Erbil, Kurdistan Region, Iraq
  • khadija khalil mustafa Department of Biology, College of Education, Salahaddin University-Erbil, Kurdistan Region, Iraq
Keywords: Enterococcus faecalis, Antimicrobial resistant, Biofilm, Virulence genes.


Enterococci are Gram-positive bacteria that cause serious nosocomial infections, including urinary tract, bloodstream infections and endocarditis. During the period of September 2018 to February 2019, forty four isolates of E. faecalis were isolated from 826 clinical specimens including; 35(5.07%) isolates of E. faecalis from urine, 7(7.60%) isolates from high vaginal swab and 2(8.69%) isolates from blood patients in different hospitals. All isolates that described above were identified depending on cultural criteria, morphological criteria, biochemical tests and further confirmed by Vitek 2 compact systems. The results of eleven antimicrobial against obtained isolates revealed that 100% of  E. faecalis were resistant to cefotaxime, vancomycin, amoxicillin and erythromycin. While, it were 100% sensitive to doxycycline, imipenem, and nitrofurantion. Whereas, most isolates were differ in their susceptibility to amikacin, gentamycin, tetracycline and azithromycin. On the other hand, the results of biofilm found that 13.63% of isolates were produce strong biofilm, 54.54% were produce moderate biofilm and 31.81% were produce weak biofilm. The results of molecular analysis by using PCR showed that isolated E. faecalis were carried 97.72%, 90.90%, 63.63% of ebpR, asa1, esp genes respectively.


Download data is not yet available.

Author Biography

khadija khalil mustafa, Department of Biology, College of Education, Salahaddin University-Erbil, Kurdistan Region, Iraq

Biology department


ABDULLAH, ZH. , & BARZANI, Kh. M. 2016. Bacteriological and Molecular Study of Gram Positive Bacteria Isolated From Thalassemic Patients in Erbil City. ZJPAS . 28 (5); 163-181.
AFONINA, I., LIM, X. N., TAN, R. & KLINE, K. A. 2018. Planktonic interference and biofilm alliance between aggregation substance and endocarditis-and biofilm-associated pili in Enterococcus faecalis. Journal of bacteriology, 200, e00361-18.
AGHDAM, M. A., BARHAGHI, M. S., AGHAZADEH, M., JAFARI, F., HAGH, M. B., HAGHDOOST, M., MEMAR, M., REZAEE, M. A. & KAFIL, H. S. 2017. Virulence genes in biofilm producer Enterococcus faecalis isolates from root canal infections. Cell Mol Biol (Noisy le Grand), 63.
AL-DULIAMI, A. A., NAUMAN, N. G., SALMAN, A. R. & HASAN, A.-R. S. 2011. Virulence factors of enterococci species isolated from nosocomial and community acquired infections. Diyala Journal For Pure Science, 7, 174-182.
AL-GHEETHI, A. A., ISMAIL, N., LALUNG, J., TALIB, A., EFAQ, A. & KADIR, M. O. A. 2013. Susceptibility for antibiotics among faecal indicators and pathogenic bacteria in sewage treated effluents. Water Practice and Technology, 8, 1-6.
AL-HUSSEINY, K. R. 2008. Bactermia and Septicemia in the ChildrenUnder three years at Al-Nasseria Province. Al-Qadisiyah Medical Journal, 4, 1-10.
AL-KHAFAJI, J. K. T., SAMAAN, S. F. & AL-SAEED, M. S. 2010. Virulence factors of Enterococcus faecalis. Medical Journal of Babylon, 7, 579-583.
AL SWEIH, N., JAMAL, W. & ROTIMI, V. 2005. Spectrum and antibiotic resistance of uropathogens isolated from hospital and community patients with urinary tract infections in two large hospitals in Kuwait. Medical Principles and Practice, 14, 401-407.
ALIPOUR, M., HAJIESMAILI, R., TALEBJANNAT, M. & YAHYAPOUR, Y. 2014. Identification and antimicrobial resistance of Enterococcus spp. isolated from the river and coastal waters in northern Iran. The Scientific World Journal, 2014.
ANAGNOSTOPOULOS, D., BOZOUDI, D. & TSALTAS, D. 2018. Enterococci isolated from cypriot green table olives as a new source of technological and probiotic properties. Fermentation, 4, 48.
ARIAS, C. A., CONTRERAS, G. A. & MURRAY, B. E. 2010. Management of multidrug-resistant enterococcal infections. Clinical microbiology and infection, 16, 555-562.
ASGHARZADEH, M., SAMADI KAFIL, H. & POURASTADI, M. 2015. Mannose Binding Lectin (MBL) and Its Clinical Significance. Journal of Babol University of Medical Sciences, 17, 61-73.
ASPRI, M., BOZOUDI, D., TSALTAS, D., HILL, C. & PAPADEMAS, P. 2017. Raw donkey milk as a source of Enterococcus diversity: Assessment of their technological properties and safety characteristics. Food Control, 73, 81-90.
BHATTY, M., CRUZ, M. R., FRANK, K. L., LAVERDE GOMEZ, J. A., ANDRADE, F., GARSIN, D. A., DUNNY, G. M., KAPLAN, H. B. & CHRISTIE, P. J. 2015. E nterococcus faecalis pCF 10‐encoded surface proteins PrgA, PrgB (aggregation substance) and PrgC contribute to plasmid transfer, biofilm formation and virulence. Molecular microbiology, 95, 660-677.
BISWAS, P. P., DEY, S., ADHIKARI, L. & SEN, A. 2014. Virulence markers of vancomycin resistant enterococci isolated from infected and colonized patients. Journal of global infectious diseases, 6, 157.
BOURGOGNE, A., SINGH, K. V., FOX, K. A., PFLUGHOEFT, K. J., MURRAY, B. E. & GARSIN, D. A. 2007. EbpR is important for biofilm formation by activating expression of the endocarditis and biofilm-associated pilus operon (ebpABC) of Enterococcus faecalis OG1RF. Journal of bacteriology, 189, 6490-6493.
CAPPUCCINO, J. G. & SHERMAN, N. 2008. Microbiology: a laboratory manual (Vol. 9). Pearson/Benjamin Cummings.
CHUANG, O. N., SCHLIEVERT, P. M., WELLS, C. L., MANIAS, D. A., TRIPP, T. J. & DUNNY, G. M. 2009. Multiple functional domains of Enterococcus faecalis aggregation substance Asc10 contribute to endocarditis virulence. Infection and immunity, 77, 539-548.
CLINICAL & INSTITUTE, L. S. 2009. Performance standards for antimicrobial susceptibility testing of anaerobic bacteria: informational supplement, Clinical and Laboratory Standards Institute (CLSI).
DAVIES, D. 2003. Understanding biofilm resistance to antibacterial agents. Nature reviews Drug discovery, 2, 114.
DAZA, R., GUTIÉRREZ, J. & PIÉDROLA, G. 2001. Antibiotic susceptibility of bacterial strains isolated from patients with community-acquired urinary tract infections. International journal of antimicrobial agents, 18, 211-215.
DE ALMEIDA, C. V., TADDEI, A. & AMEDEI, A. 2018. The controversial role of Enterococcus faecalis in colorectal cancer. Therapeutic advances in gastroenterology, 11, 1756284818783606.
EL-KERSH, T. A., MARIE, M. A., AL-SHEIKH, Y. A., AL-AGAMY, M. H. & AL BLOUSHY, A. A. 2016. Prevalence and risk factors of early fecal carriage of Enterococcus faecalis and Staphylococcus spp and their antimicrobial resistant patterns among healthy neonates born in a hospital setting in central Saudi Arabia. Saudi Med J, 37, 279-286.
ENDO, M. S., SIGNORETTI, F., KITAYAMA, V. S., MARINHO, A., MARTINHO, F. C. & GOMES, B. 2014. Culture and molecular detection of Enterococcus faecalis from patients with failure endodontic treatment and antimicrobial susceptibility of clinical isolates. Braz Dent Sci, 17, 83-91.
FUKA, M. M., MAKSIMOVIC, A. Z., TANUWIDJAJA, I., HULAK, N. & SCHLOTER, M. 2017. Characterization of enterococcal community isolated from an Artisan Istrian raw milk cheese: Biotechnological and safety aspects. Food technology and biotechnology, 55, 368.
GARCÍA-SOLACHE, M. & RICE, L. B. 2019. The Enterococcus: a model of adaptability to its environment. Clinical microbiology reviews, 32, e00058-18.
HEIKENS, E., BONTEN, M. J. & WILLEMS, R. J. 2007. Enterococcal surface protein Esp is important for biofilm formation of Enterococcus faecium E1162. Journal of bacteriology, 189, 8233-8240.
HEMRAJ, V., DIKSHA, S. & AVNEET, G. 2013. A review on commonly used biochemical test for bacteria. Innovare J Life Sci, 1, 1-7.
HIGUITA, N. I. A. & HUYCKE, M. M. 2014. Enterococcal disease, epidemiology, and implications for treatment. Enterococci: From Commensals to Leading Causes of Drug Resistant Infection [Internet]. Massachusetts Eye and Ear Infirmary.
HØIBY, N., BJARNSHOLT, T., GIVSKOV, M., MOLIN, S. & CIOFU, O. 2010. Antibiotic resistance of bacterial biofilms. International journal of antimicrobial agents, 35, 322-332.
IGELTJØRN, L. 2009. Molecular and biochemical characterisation of naturally occurring hyperexpressed and mutated extended spectrum AmpC beta-lactamases in Norwegian clinical isolates of Escherichia coli. Universitetet i Tromsø.
JAYASUNDARA, N. S. 2014. An investigation of Staphylococcus aureus and related species from flood affected and other environmental sources. Queensland University of Technology.
KAFIL, H. S. & MOBAREZ, A. M. 2015. Assessment of biofilm formation by enterococci isolates from urinary tract infections with different virulence profiles. Journal of King Saud University-Science, 27, 312-317.
KEHINDE, E. O., AL-MAGHREBI, M., SHEIKH, M. & ANIM, J. T. 2013. Combined ciprofloxacin and amikacin prophylaxis in the prevention of septicemia after transrectal ultrasound guided biopsy of the prostate. The Journal of urology, 189, 911-915.
KENT, V. 2013. Cell wall architecture and the role of wall teichoic acid in Staphylococcus aureus. University of Sheffield.
KRISTICH, C. J., RICE, L. B. & ARIAS, C. A. 2014. Enterococcal infection—treatment and antibiotic resistance. Enterococci: From commensals to leading causes of drug resistant infection [Internet]. Massachusetts Eye and Ear Infirmary.
KUDO, M., NOMURA, T., YOMODA, S., TANIMOTO, K. & TOMITA, H. 2014. Nosocomial infection caused by vancomycin‐susceptible multidrug‐resistant Enterococcus faecalis over a long period in a university hospital in Japan. Microbiology and immunology, 58, 607-614.
MATHUR, T., SINGHAL, S., KHAN, S., UPADHYAY, D., FATMA, T. & RATTAN, A. 2006. Detection of biofilm formation among the clinical isolates of staphylococci: an evaluation of three different screening methods. Indian journal of medical microbiology, 24, 25.
MISHRA, V., NAG, V. L., TANDON, R. & AWASTHI, S. 2010. Response Surface Methodology-Based Optimisation of Agarose Gel Electrophoresis for Screening and Electropherotyping of Rotavirus. Applied biochemistry and biotechnology, 160, 2322-2331.
MOHAMED, J. A. & MURRAY, B. E. 2005. Lack of correlation of gelatinase production and biofilm formation in a large collection of Enterococcus faecalis isolates. Journal of clinical microbiology, 43, 5405-5407.
MOHAMMADI, F., GHAFOURIAN, S., MOHEBI, R., TAHERIKALANI, M., PAKZAD, I., VALADBEIGI, H., HATAMI, V. & SADEGHIFARD, N. 2015. Enterococcus faecalis as multidrug resistance strains in clinical isolates in Imam Reza Hospital in Kermanshah, Iran. British journal of biomedical science, 72, 182-184.
NAVAS, M., PINCUS, D. H., WILKEY, K., SERCIA, L., LASALVIA, M., WILSON, D., PROCOP, G. W. & RICHTER, S. S. 2014. Identification of aerobic Gram-positive bacilli by use of Vitek MS. Journal of clinical microbiology, 52, 1274-1277.
O’DRISCOLL, T. & CRANK, C. W. 2015. Vancomycin-resistant enterococcal infections: epidemiology, clinical manifestations, and optimal management. Infection and drug resistance, 8, 217.
PHILIPPE, D. & DEBORAH, C. 2010. Nanodrop microvolume quantitation of nucleic acid. Journal of Visualized Experiment, 45, 2565.
POURCEL, N. G., SPARO, M. D., CORSO, A., DELPECH, G., GAGETTI, P. S., DE LUCA, M. M., BERNSTEIN, J. C., SCHELL, C. M. B., LISARRAGUE, S. & BASUALDO FARJAT, J. A. 2017. Molecular genetic profiling of clinical and foodborne strains of enterococci with high level resistance to gentamicin and vancomycin.
SAMADI, N., PAKZAD, I., SEFIDAN, A. M., HOSAINZADEGAN, H. & TANOMAND, A. 2015. Study of aminoglycoside resistance genes in Enterococcus and Salmonella strains isolated from Ilam and Milad hospitals, Iran. Jundishapur journal of microbiology, 8.
SANGEETHA, B. G., JAYAPRAKAS, C. A., SIJI, J. V., RAJITHA, M., SHYNI, B. & MOHANDAS, C. 2016. Molecular characterization and amplified ribosomal DNA restriction analysis of entomopathogenic bacteria associated with Rhabditis (Oscheius) spp. 3 Biotech, 6, 32.
SARAH, A., SAIF, Q., RUHI, K., ASFIA, S., MEHER, R. & SHAHZAD, H. F. 2015. Semen culture in patients with chronic prostatitis syndrome: A valuable diagnostic tool. International Journal of Current Microbiology and Applied Sciences, Special, 236-242.
SHANKAR, V., BAGHDAYAN, A. S., HUYCKE, M. M., LINDAHL, G. & GILMORE, M. S. 1999. Infection-derived Enterococcus faecalisstrains are enriched in esp, a gene encoding a novel surface protein. Infection and immunity, 67, 193-200.
SHARMA, K. 2007. Manual of Microbiology, Ane Books Pvt Ltd.
SHRIDHAR, S. & DHANASHREE, B. 2019. Antibiotic Susceptibility Pattern and Biofilm Formation in Clinical Isolates of Enterococcus spp. Interdisciplinary perspectives on infectious diseases, 2019.
SILVA, N., IGREJAS, G., GONÇALVES, A. & POETA, P. 2012. Commensal gut bacteria: distribution of Enterococcus species and prevalence of Escherichia coli phylogenetic groups in animals and humans in Portugal. Annals of Microbiology, 62, 449-459.
SINGH, K. V., NALLAPAREDDY, S. R., SILLANPÄÄ, J. & MURRAY, B. E. 2010. Importance of the collagen adhesin ace in pathogenesis and protection against Enterococcus faecalis experimental endocarditis. PLoS pathogens, 6, e1000716.
STĘPIEŃ-PYŚNIAK, D., MAREK, A., BANACH, T., ADASZEK, Ł., PYZIK, E., WILCZYŃSKI, J. & WINIARCZYK, S. 2016. Prevalence and antibiotic resistance of Enterococcus strains isolated from poultry. Acta Veterinaria Hungarica, 64, 148-163.
STRATEV, D., DASKALOV, H. & VASHIN, I. 2015. Characterisation and determination of antimicrobial resistance of β-haemolytic Aeromonas spp. isolated from common carp (Cyprinus carpio L.). Revue de médecine vétérinaire, 166, 54-61.
STRATEVA, T., ATANASOVA, D., SAVOV, E., PETROVA, G. & MITOV, I. 2016. Incidence of virulence determinants in clinical Enterococcus faecalis and Enterococcus faecium isolates collected in Bulgaria. Brazilian Journal of Infectious Diseases, 20, 127-133.
SUBRAMANIAN, M. R., TALLURI, S. & CHRISTOPHER, L. P. 2015. Production of lactic acid using a new homofermentative E nterococcus faecalis isolate. Microbial biotechnology, 8, 221-229.
TALEBI, M., MOGHADAM, N. A., MAMOOII, Z., ENAYATI, M., SAIFI, M. & POURSHAFIE, M. R. 2015. Antibiotic Resistance and Biofilm Formation of Enterococcus faecalis in Patient and Environmental Samples. Blood, 14, 24.
UDO, E. E., AL-SWEIH, N., PHILLIPS, O. A. & CHUGH, T. D. 2003. Species prevalence and antibacterial resistance of enterococci isolated in Kuwait hospitals. Journal of medical microbiology, 52, 163-168.
ULLAH, O., KHATTAK, M., HASAN, F., RAJA, N., HUSSAIN, S., AKHTAR, N. & SHAH, A. A. 2015. Vancomycin Resistant Enterococcal Infections in Tertiary Care Hospitals of Islamabad and Rawalpindi, Pakistan. Pakistan Journal of Zoology, 47.
VAN TYNE, D. & GILMORE, M. S. 2014. Friend turned foe: evolution of enterococcal virulence and antibiotic resistance. Annual review of microbiology, 68, 337-356.
YANG, H. K. & JUETT, B. W. 2016. Preliminary Report: Prevalence of vancomycin-resistant Enterococcus faecalis in public restrooms in central Kentucky. Bios, 87, 150-154.
YANG, Y., LI, W., HOU, B. & ZHANG, C. 2018. Quorum sensing LuxS/autoinducer-2 inhibits Enterococcus faecalis biofilm formation ability. Journal of Applied Oral Science, 26.
YÜCEER, Ö. & ÖZDEN TUNCER, B. 2015. Determination of Antibiotic Resistance and Biogenic Amine Production of Lactic Acid Bacteria Isolated from Fermented T urkish Sausage (Sucuk). Journal of Food Safety, 35, 276-285.
ZOLETTI, G. O., PEREIRA, E. M., SCHUENCK, R. P., TEIXEIRA, L. M., SIQUEIRA JR, J. F. & DOS SANTOS, K. R. N. 2011. Characterization of virulence factors and clonal diversity of Enterococcus faecalis isolates from treated dental root canals. Research in Microbiology, 162, 151e158.
ZOU, J. & SHANKAR, N. 2016. Surface protein Esp enhances pro-inflammatory cytokine expression through NF-κB activation during enterococcal infection. Innate immunity, 22, 31-39.
How to Cite
H. Khdir, K. and mustafa, khadija (2020) “Molecular and Bacteriological Study of Enterococcus faecalis Isolated from Different Clinical Sources”, Zanco Journal of Pure and Applied Sciences, 32(2), pp. 157-166. doi: 10.21271/ZJPAS.32.2.17.
Biology and Medical Researches