The hylEfmgene in pHylEfm of Enterococcus faecium is not required in pathogenesis of murine peritonitis

BMC Microbiology

Research Article

Maria F Mojica¹  Maria C Montealegre¹  Diana Panesso²  Cesar A Arias²  Sandra Rincón²  Kavindra V Singh³  Barbara E Murray⁴  Louis B Rice⁵ 

[1] Department of Internal Medicine, Division of Infectious Diseases, Center for the Study of Emerging and Reemerging Pathogens, Houston, TX, USA;Laboratory for Antimicrobial Research, University of Texas Medical School at Houston, Houston, TX, USA;Centro Internacional de Entrenamiento e Investigaciones Médicas (CIDEIM), Cali, Colombia;Department of Internal Medicine, Division of Infectious Diseases, Center for the Study of Emerging and Reemerging Pathogens, Houston, TX, USA;Laboratory for Antimicrobial Research, University of Texas Medical School at Houston, Houston, TX, USA;Molecular Genetics and Antimicrobial Resistance Unit, Universidad El Bosque, Bogotá, Colombia;Department of Internal Medicine, Division of Infectious Diseases, Center for the Study of Emerging and Reemerging Pathogens, Houston, TX, USA;Laboratory of Enterococcal Research, University of Texas Medical School at Houston, Houston, TX, USA;Department of Internal Medicine, Division of Infectious Diseases, Center for the Study of Emerging and Reemerging Pathogens, Houston, TX, USA;Laboratory of Enterococcal Research, University of Texas Medical School at Houston, Houston, TX, USA;Department of Microbiology and Molecular Genetics, University of Texas Medical School at Houston, Houston, TX, USA;Medical and Research Services, Louis Stokes Cleveland Department of Veterans Medical Center, Cleveland, OH, USA;Department of Medicine, Case Western Reserve University, School of Medicine, Cleveland, OH, USA;

关键词: Brain Heart Infusion;    Glycosyl Hydrolase;    Brain Heart Infusion Broth;    Brain Heart Infusion Agar;    Hyaluronidase Activity;   

DOI  :  10.1186/1471-2180-11-20

 received in 2010-09-17, accepted in 2011-01-25,  发布年份 2011

来源: Springer

【 摘 要 】

BackgroundPlasmids containing hylEfm(pHylEfm) were previously shown to increase gastrointestinal colonization and lethality of Enterococcus faecium in experimental peritonitis. The hylEfmgene, predicting a glycosyl hydrolase, has been considered as a virulence determinant of hospital-associated E. faecium, although its direct contribution to virulence has not been investigated. Here, we constructed mutants of the hylEfm-region and we evaluated their effect on virulence using a murine peritonitis model.ResultsFive mutants of the hylEfm-region of pHylEfmTX16 from the sequenced endocarditis strain (TX16 [DO]) were obtained using an adaptation of the PheS* system and were evaluated in a commensal strain TX1330RF to which pHylEfmTX16 was transferred by mating; these include i) deletion of hylEfmonly; ii) deletion of the gene downstream of hylEfm(down) of unknown function; iii) deletion of hylEfmplus down; iv) deletion of hylEfm-down and two adjacent genes; and v) a 7,534 bp deletion including these four genes plus partial deletion of two others, with replacement by cat. The 7,534 bp deletion did not affect virulence of TX16 in peritonitis but, when pHylEfmTX16Δ7,534 was transferred to the TX1330RF background, the transconjugant was affected in in vitro growth versus TX1330RF(pHylEfmTX16) and was attenuated in virulence; however, neither hylEfmnor hylEfm-down restored wild type function. We did not observe any in vivo effect on virulence of the other deletions of the hylEfm-regionConclusionsThe four genes of the hylEfmregion (including hylEfm) do not mediate the increased virulence conferred by pHylEfmTX16 in murine peritonitis. The use of the markerless counterselection system PheS* should facilitate the genetic manipulation of E. faecium in the future.

【 授权许可】

Unknown   
© Panesso et al; licensee BioMed Central Ltd. 2011. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.