Genetic Characterization of a Novel Composite Transposon Carrying armA and aac(6)-Ib Genes in an Escherichia coli Isolate from Egypt


Share / Export Citation / Email / Print / Text size:

Polish Journal of Microbiology

Polish Society of Microbiologists

Subject: Microbiology


ISSN: 1733-1331
eISSN: 2544-4646





Volume / Issue / page

Related articles

VOLUME 66 , ISSUE 2 (June 2017) > List of articles

Genetic Characterization of a Novel Composite Transposon Carrying armA and aac(6)-Ib Genes in an Escherichia coli Isolate from Egypt

Mona T. Kashef * / Omneya M. Helmy

Keywords : 16S rRNA methyl transferases, aminoglycosides, armA, β-lactmase

Citation Information : Polish Journal of Microbiology. Volume 66, Issue 2, Pages 163-169, DOI:

License : (CC BY-NC-ND 4.0)

Received Date : 28-June-2016 / Accepted: 17-September-2016 / Published Online: 28-June-2017



Aminoglycosides are used in treating a wide range of infections caused by Gram-positive and Gram-negative bacteria; however, amino­glycoside resistance is common and occurs by several mechanisms. Among these mechanisms is bacterial rRNA methylation by the 16S rRNA methyl transferase (16S-RMTase) enzymes; but data about the spread of this mechanism in Egypt are scarce. Cephalosporins are the most commonly used antimicrobial agents in Egypt; therefore, this study was conducted to determine the frequency of 16S-RMTase among third generation cephalosporin-resistant clinical isolates in Egypt. One hundred and twenty three cephalosporin resistant Gram-negative clinical isolates were screened for aminoglycosides resistance by the Kirby Bauer disk diffusion method and tested for possible production of 16S-RMTase. PCR testing and sequencing were used to confirm the presence of 16S-RMTase and the associated antimicrobial resist­ance determinants, as well as the genetic region surrounding the armA gene. Out of 123 isolates, 66 (53.66%) were resistant to at least oneaminoglycoside antibiotic. Only one Escherichia coli isolate (E9ECMO) which was totally resistant to all tested aminoglycosides, was confirmed to have the armA gene in association with blaTEM-1, blaCTX-M-15, blaCTX-M-14 and aac(6)-Ib genes. The armA gene was found to be carried on a large A/C plasmid. Genetic mapping of the armA surrounding region revealed, for the first time, the association of armA with aac(6)-Ib on the same transposon. In conclusion, the isolation frequency of 16S-RMTase was low among the tested aminoglycoside-resistant clinical samples. However, a novel composite transposon has been detected conferring high-level aminoglycosides resistance.

Content not available PDF Share



Bogaerts P., M. Galimand, C. Bauraing, A. Deplano, R. Vanhoof, R. De Mendonca, H. Rodriguez-Villalobos, M. Struelens andY. Glupczynski. 2007. Emergence of ArmA and RmtB aminoglycoside resistance16S rRNA methylases in Belgium. J. Antimicrob. Chemother. 59: 459–464.


Carattoli A. 2009. Resistance plasmid families in Enterobacteriaceae. Antimicrob. Agents Chemother. 53: 2227–2238.


Cattoir V., L. Poirel, V. Rotimi, C.J. Soussy and P. Nordmann. 2007. Multiplex PCR for detection of plasmid-mediated quinolone resistance qnr genes in ESBL-producing enterobacterial isolates.J. Antimicrob. Chemother. 60:394–397.


Clinical and Laboratory Standards Institute (CLSI). 2012a. Performance standards for antimicrobial disk susceptibility tests,eleventh edition M02-A11. Clinical and Laboratory Standards Institute. Wayne, PA, USA.


Clinical and Laboratory Standards Institute (CLSI). 2012b.Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically; approved standard ninth edition M07-A9. Clinical and Laboratory Standards Institute. Wayne, PA, USA.


Dallenne C., A. Da Costa, D. Decré, C. Favier and G. Arlet. 2010. Development of a set of multiplex PCR assays for the detectionof genes encoding important β-lactamases in Enterobacteriaceae.J. Antimicrob. Chemother. 65: 490–495.


Davis M.A., K.N. Baker, L.H. Orfe, D.H. Shah, T.E. Besser and D.R. Call. 2010. Discovery of a gene conferring multiple-aminoglycoside resistance in Escherichia coli. Antimicrob. Agents Chemother. 54: 2666–2669.


Doi Y., K. Yokoyama, K. Yamane, J. Wachino, N. Shibata, T. Yagi, K. Shibayama, H. Kato and Y. Arakawa. 2004. Plasmid-mediated 16S rRNA methylase in Serratia marcescens conferring high-level resistance to aminoglycosides. Antimicrob. Agents Chemother. 48: 491–496.


Doi Y. and Y. Arakawa. 2007. 16S Ribosomal RNA methylation: emerging resistance mechanism against Aminoglycosides. Clin. Infect. Dis. 45: 88–94.


Doi Y., D.O. Garcia, J. Adams and D.L. Paterson. 2007. Coproduction of novel 16S rRNA methylase RmtD and metallo-β-lactamase SPM-1 in a panresistant Pseudomonas aeruginosa isolate fromBrazil. Antimicrob. Agents Chemother. 51: 852–856.


Fritsche T.R., M. Castanheira, G.H. Miller, R.N. Jones andE.S. Armstrong. 2008. Detection of methyltransferases conferring high-level resistance to aminoglycosides in Enterobacteriaceae from Europe, North America, and Latin America. Antimicrob. AgentsChemother. 52: 1843–1845.


Galani I., M. Souli, T. Panagea, G. Poulakou, K. Kanellakopoulouand H. Giamarellou. 2012. Prevalence of 16S rRNA methylase genes in Enterobacteriaceae isolates from a Greek University Hospital. Clin. Microbiol. Infect. 18: E52–E54.


Galimand M., P. Courvalin and T. Lambert. 2003. Plasmid-mediated high-level resistance to aminoglycosides in Enterobacteriaceae due to 16S rRNA methylation. Antimicrob. Agents Chemother. 47: 2565–2571.


Galimand M., S. Sabtcheva, P. Courvalin and T. Lambert. 2005. Worldwide disseminated armA aminoglycoside resistance methylase gene is borne by composite transposon Tn1548. Antimicrob. Agents Chemother. 49: 2949–2953.


Galimand M., P. Courvalin and T. Lambert. 2012. RmtF, a new member of the aminoglycoside resistance 16S rRNA N7 G1405 methyl-transferase family. Antimicrob. Agents Chemother. 56: 3960–3962.


Gołebiewski. M., I. Kern-Zdanowicz, M. Zienkiewicz, M. Adamczyk, J. Zylinska, A. Baraniak, M. Gniadkowski, J. Bardowski and P. Cegłowski. 2007. Complete nucleotide sequence of the pCTX-M3 plasmid and its involvement in spread of the extended-spectrum β-lactamase gene blaCTX-M-3. Antimicrob. Agents Chemother. 51: 3789–3795.


González-Zorn B., A. Catalan, J.A. Escudero, L. Domínguez,T. Teshager, C. Porrero and M.A. Moreno. 2005a. Genetic basis for dissemination of armA. J. Antimicrob. Chemother. 56: 583–585.


González-Zorn B., T. Teshager, M. Casas, M.C. Porrero,M.A. Moreno, P. Courvalin and L. Domínguez. 2005b. armA and aminoglycoside resistance in Escherichia coli. Emerg. Infect. Dis. 11: 954–956.


Granier S.A., L. Hidalgo, A. San Millan, J.A. Escudero, B. Gutierrez, A. Brisabois and B. Gonzalez-Zorn. 2011. ArmA methyltransferase in a monophasic Salmonella enteric isolate from food. Antimicrob. Agents Chemother. 55: 5262–5266.


Hassan A.M., O. Ibrahim and M. El Guinaidy. 2011. Surveillance of antibiotic use and resistance in orthopaedic department in an Egyptian University Hospital. Int. J. Infect. Control. 7: 1–10.


Johnson T.J., Y.M. Wannemuehler, S.J. Johnson, C.M. Logue,D.G. White, C. Doetkott and L.K. Nolan. 2007. Plasmid replicon typing of commensal and pathogenic Escherichia coli isolates. Appl. Environ. Microbiol. 73:1976–1983.


Kang H.Y., K.Y. Kim, J. Kim, J.C. Lee, Y.C. Lee, D.T. Cho and S.Y. Seol. 2008. Distribution of conjugative-plasmid-mediated 16S rRNA methylase genes among amikacin-resistant Enterobacteriaceae isolates collected in 1995 to 1998 and 2001 to 2006 at a University Hospital in South Korea and identification of conjugative plasmids mediating dissemination of 16S rRNA Methylase. J. Clin. Microbiol. 46: 700–706.


Kashif M.T., A.S. Yassin and Ael-D. Hosny. 2012. Detectionof AmpC beta-lactamases using sodium salicylate. J. Microbiol. Methods. 91: 354–357.


Lee H., D. Yong, J.H. Yum, K.H. Roh, K. Lee, K. Yamane, Y. Arakawa and Y. Chong. 2006. Dissemination of 16S rRNA methylase-mediated highly amikacin-resistant isolates of Klebsiella pneumoniae and Acinetobacter baumannii in Korea. Diagn. Microbiol. Infect. Dis. 56: 305–312.


Magnet S. and J.S. Blanchard. 2005. Molecular insights into aminoglycoside action and resistance. Chem. Rev.105: 477–498.


Park C.H., A. Robicsek, G.A. Jacoby, D. Sahm and D.C Hooper. 2005. Prevalence in the United States of aac(6)-Ib-cr encoding a ciprofloxacin-modifying enzyme. Antimicrob. Agents Chemother. 50: 3953–3955.


Poirel L., L. Dortet, S. Bernabeu and P. Nordmann. 2012. Genetic features of blaNDM-1-positive Enterobacteriaceae. Antimicrob. Agents Chemother. 55: 5403–5407.


Wachinoa J. and Y. Arakawa. 2012. Exogenously acquired 16S rRNA methyltransferases found in aminoglycoside-resistant pathogenic Gram-negative bacteria: an update. Drug Resist. Updat. 15: 133–148.


Wachino J., K. Yamane, K. Shibayama, H. Kurokawa, N. Shibata, S. Suzuki, Y. Doi, K. Kimura, Y. Ike and Y. Arakawa. 2006. Novel plasmid-mediated 16S rRNA methylase, RmtC, found in a Proteus mirabilis isolate demonstrating extraordinary high-level resistance against various aminoglycosides. Antimicrob. Agents Chemother. 50: 178–184.


World Health Organization (WHO). 2011. Critically important antimicrobials for human medicine, 2nd revision. World Health Organization. Geneva., 2015.02.20.


Xia Q., H. Wang, A. Zhang, T. Wang and Y. Zhang. 2011. Prevalence of 16S rRNA methylase conferring high-level aminoglycoside resistance in Escherichia coli in China. Int. J. Antimicrob. Agents. 37: 385–388.


Yamane K., J. Wachino, S. Suzuki, N. Shibata, H. Kato, K. Shibayama, K. Kimura, K. Kai, S. Ishikawa, Y. Ozawa and others. 2007. 16S rRNA Methylase-producing, Gram-negative pathogens, Japan. Emerg. Infect. Dis. 13: 642–646.


Yamane K., J. Wachino, S. Suzuki and Y. Arakawa. 2008. Plasmid-mediated qepA gene among Escherichia coli clinical isolates from Japan. Antimicrob. Agents Chemother. 52: 1564–1566.


Yang J., L. Ye, W. Wang, Y. Luo, Y. Zhang and L. Han. 2011. Diverse prevalence of 16S rRNA methylase genes armA and rmtB amongst clinical multidrug-resistant Escherichia coli and Klebsiella pneumoniae isolates. Int. J. Antimicrob. Agents. 38: 48–351.


Yokoyama K., Y. Doi, K. Yamane, H. Kurokawa, N. Shibata,K. Shibayama, T. Yagi, H. Kato and Y. Arakawa. 2003. Acquisition of 16S rRNA methylase gene in Pseudomonas aeruginosa. Lancet 362: 1888–1893.


Zhang Y., H. Zhou, X.Q. Shen, P. Shen, Y.S. Yu and L.J. Li. 2008. Plasmid-borne armA methylase gene, together with blaCTX-M-15 and blaTEM-1, in a Klebsiella oxytoca isolate from China. J. Med. Microbiol. 57: 1273–1276.