Molecular Characterization and Distribution of Virulence Determinants Among Enterococcus faecalis from Ready-to-Eat Food Outlets
[1]
Olawale A. K., Department of Applied Sciences, Osun State Polytechnic, Iree, Nigeria.
[2]
Onasanya A., Department of Chemical Sciences, Afe Babalola University, Ado-Ekiti, Nigeria.
[3]
Oyelakin O. O., Biotechnology Centre, Federal University of Agriculture, Abeokuta, Nigeria.
[4]
Olawale A. O., Department of Mathematics and Statistics, Osun State Polytechnic, Iree, Nigeria.
[5]
Olaolu A. O., Department of Biomedical Sciences, Ladoke Akintola University of Technology, Osogbo, Nigeria.
[6]
Oje O. J., Department of Food Technology, Federal Polytechnic, Ado-Ekiti, Nigeria.
[7]
David O. M., Department of Microbiology, Ekiti State University, Ado-Ekiti, Nigeria.
[8]
Famurewa O., Department of Microbiology, Ekiti State University, Ado-Ekiti, Nigeria.
The study investigates the incidence, characterization and distribution of virulence determinants among Enterococcus faecalis isolates from ready-to-eat food origin. Twenty E. faecalis isolates from different food canteen samples in Osun State, Nigeria between 2009 and 2010 were selected from the previous work. PCR was performed using previously reported primers with an iCycler apparatus and Takara Ex Taq as the DNA polymerase. Distribution of Five genes coding virulence determinants; gelatinase (gelA), aggregation substance (asa1), cytolysin activator (cylA), enterococcal surface protein (esp) and collagen-binding protein (ace) were revealed among isolates. The amplified fragments were purified using the ExoSAP-IT and the nucleotide sequence of both strands was determined using Genetic Analyzer with the BigDye Terminator cycle sequencing kit. The sequences were then assembled with Sequencher and the DNA alignment was examined using the Basic Local Alignment Search Tool. The genetic relationship of the virulence determinants among E. faecalis strains was analyzed by constructing dendograms using the statistical package, Molecular Evolutionary Genetics Analysis 4(MEGA4) software. Results obtained from virulence determinants genotype and virulence sequence typing dendograms revealed 2 major virulence groups each (GEf1 and GEf2) and (SEf1 and SEf2), respectively. GEf1 has two subgroups (GEf1a; GEf1b) and GEf2 (GEf2a, GEf2b). Some isolates from different eateries were identical in their degree of virulence. Similar virulence identity observed inter-canteens suggests possible pathogen migration between the canteens and long-term survival. SEf1 has each strain separated in the ascending order of high virulence levels, from EFC59 to EFT 194. There was no correlation between sources and degree of virulence among the strains. SEf2 consists one isolate EFS 18 with lower virulence potential. Presence of potentially virulent E. faecalis in the study areas portends danger for reservoir of high antibiotic resistance pathogens. This calls for adoption of stringent infection control measures.
Molecular Characterization, DNA Sequence, Virulence Determinant, Enterococcus faecalis
[1]
Barbosal, D., Fram, D., Castrucci, F. M., Taminato, M., Godoy-Martinez, P., Freitas, M. C. S., Belasco, A., Sesso, R., Pacheco-Silva, A., Pignatari, A. C. (2010). Cross-transmission of vancomycin resistant Enterococcus in patients undergoing dialysis and kidney transplant. Braz J Med Biol Res. 43(1): 115-119.
[2]
Creti, R.M., Imperi, L., Bertucini, F., Fabretti, G., Orefici, R., Di Rosa, and Baldassari, L. (2004). Survey for virulence determinants among Enterococcus faecalis isolated from different sources. J. Med. Microbiol. 53:13-20.
[3]
Aher, C. S. (2014). Vancomycin resistant Enterococci: an emerging threat. Int J. Curr. Microbiol. Appl. Sci. 3(2): 14-19.
[4]
Gomes, B. C., Esteves, C. T., Palazzo, I. C., Darini, A. L., Felis, G. E., Sechi, L. A., Franco, B. D. and DeMartins, E. C. (2008). Prevalence and characterization of Enterococcus spp. isolated from Brazilian foods. Food Microbiol. 25(5):668-675.
[5]
Kisson, S., Akpaka, P. E., and Swanston W. H. (2015). Vancomycin Resistant Enterococci infections in Trinidad and Tobago. Bri. Microbiol. Res. J. 9(3): 1-8.
[6]
Murray, B. E. 2000. Vancomycin-resistant enterococcal infections. N. Engl. J. Med. 342:710–721.
[7]
O”Driscoll, T. and Crank C. W. (2015). Vancomycin resistant enterococcal infections: epidemiology, clinical manifestations, and optimal management. Inf. Drug. Resist. 8: 217-230.
[8]
Olawale, A. K., Onasanya A., Oyelakin O.O., David O.M, and Famurewa O. (2014). Enterococcus faecalis isolates of food origin and detection of their virulence determinant genes in Osun State, Nigeria. Microbiol. Res. Int. 2(2): 18-27.
[9]
Oliveira, D. C., Tomasz, A. and de Lencastre. H. (2002). Secrets of success of a human pathogen: molecular evolution of pandemic clones of meticillinresistant Staphylococcus aureus. Lancet Infect. Dis. 2:180–189.
[10]
Onasanya, A., Basso, A., Somado, E., Gasore, E. R. and Nwilene, F. E. (2010). Development of a combined molecular diagnostic and DNA fingerprinting technique for rice bacteria pathogensin Africa. Biotechnology. 9: 89-105.
[11]
Paulsen, I. T., Banerjei, L., Myers, G. S., Nelson, K. E., Seshadri, R., Read, T. D., Fouts, D. E., Eisen, J. A., Gill, S. R., Heidelberg, J. F., Tettelin, H. Dodson, R. J., Umayam, L., Brinkac, L., Beanan, M., Daugherty, S., DeBoy, R. T., Durkin, S., Kolonay, J., Madupu, R., Nelson, W., Vamathevan, J., Tran, B., Upton, J., Hansen, T., Shetty, J., Khouri, H., Utterback, T., Radune, D., Ketchum, K. A., Dougherty, B. A. and Fraser. C. M. (2003). Role of mobile DNA in the evolution of vancomycin-resistant Enterococcus faecalis. Science 299: 2071–2074.
[12]
Rybaka, A., Hall, D., Steed M. E., Arias, C. A., Murray, B. E. and Michael, J. (2012). Evaluation of Standard- and High-Dose Daptomycin versus Linezolid against Vancomycin-Resistant Enterococcus isolates in an in vitro Pharmacokinetic/Pharmacodynamic model with simulated endocardial vegetations. Antimicrob. Agents Chemother. 56(6): 3174–3180.
[13]
Shinde, R. S., Koppikar, G. V. and Oommen, S. (2012). Characterization and antimicrobial susceptibility pattern of clinical isolates of Enterococci at a tertiary care hospital in Mumbai, India. Ann. Trop. Med. Publ. Health. 5(2): 85-88.
[14]
Tsai, H., Liao, C., Chen, Y., Lu, C., Hua Huang, C., Lu, C., Chuang, Y., Tsao, S., Chen, Y., Liu, Y., Chen, W., Jang, T., Lin, H., Pan, C., Yang, J., Kung, H., Liu, C., Cheng, Y., Sun, J., Wang, L., Ko, W., Yu, K., Chiang, P., Lee, M., Lee, C., Hsu, G. and Ren, P. (2012). trends in susceptibility of vancomycin-resistant Enterococcus faecium to Tigecycline, daptomycin, and Linezolid and Molecular epidemiology of the Isolates: Results from the tigecycline in vitro surveillance in Taiwan (TIST) study, 2006 to 2010. Antimicrob Agents Chemother. 56(6): 3402–3405.
[15]
Weigel, L. M., Clewell, D. B., Gill, S. R., Clark, N. C., McDougal, L. K., Flannagan, S. E., Kolonay, J. F., Shetty, J., Killgore, G. E. and Tenover, F. C. (2003). Genetic analysis of a high-level vancomycin-resistant isolate of Staphylococcus aureus. Science. 302: 1569–1571.
