Fachbereich Veterinärmedizin



    Detection and new genetic environment of the pleuromutilin-lincosamide-streptogramin A resistance gene lsa(E) in methicillin-resistant Staphylococcus aureus of swine origin (2013)

    Zeitschriftenartikel / wissenschaftlicher Beitrag
    Li, Beibei
    Wendlandt, Sarah
    Yao, Jiannan
    Liu, Yiqiu
    Zhang, Qing
    Shi, Zixue
    Wei, Jianchao
    Shao, Donghua
    Schwarz, Stefan (WE 7)
    Wang, Shaohui
    Ma, Zhiyong
    The Journal of antimicrobial chemotherapy; 68(6) — S. 1251–1255
    ISSN: 0305-7453
    DOI: 10.1093/jac/dkt015
    Pubmed: 23386262
    Institut für Mikrobiologie und Tierseuchen

    Robert-von-Ostertag-Str. 7-13
    Gebäude 35
    14163 Berlin
    +49 30 838 51840 / 51843

    Abstract / Zusammenfassung

    To investigate the genetic basis of pleuromutilin resistance in porcine methicillin-resistant Staphylococcus aureus (MRSA) and to map the genetic environment of the identified plasmid-borne resistance gene.

    Seventy porcine MRSA isolates, which exhibited high MICs of tiamulin, valnemulin and retapamulin, were investigated for pleuromutilin resistance genes and mutations. They were characterized by staphylococcal cassette chromosome mec (SCCmec) typing, spa typing and multilocus sequence typing (MLST). Plasmid DNA was extracted from the lsa(E)-positive strains and transferred to S. aureus RN4220 for selection of resistance plasmids. The plasmid-borne lsa(E) gene region was sequenced and 10 overlapping PCR assays for the analysis of the genetic environment of lsa(E) were developed.

    All 70 MRSA isolates were ST9 (MLST)-t899 (spa)-IVa (SCCmec). Sixteen isolates carried the lsa(E) gene; all others were negative for known pleuromutilin resistance mechanisms. An lsa(E)-carrying plasmid of ∼41 kb was detected in a single isolate. Sequence analysis revealed that the lsa(E) gene was located in a multiresistance gene cluster, which showed partial homology to clusters identified in MRSA, methicillin-susceptible S. aureus (MSSA) and Enterococcus faecalis. PCR analysis of the remaining isolates revealed a partly deleted multiresistance gene cluster in 6/15 isolates and solely the lsa(E) gene without the known flanking regions in 9/15 isolates.

    We identified the pleuromutilin-lincosamide-streptogramin A resistance gene lsa(E) in porcine MRSA isolates. The multiresistance gene cluster in which lsa(E) was located differed from the previously described ones found in human MRSA/MSSA or in E. faecalis. The location of lsa(E) on a multiresistance plasmid facilitates its persistence and dissemination.