Paula Espinal1,2, Alix Pantel2,3, Dora Rolo1, Sara Marti4,5, Rafael López-Rojas6, Younes Smani6, Jerónimo Pachón6, Jordi Vila1, Jean-Philippe Lavigne2,3. 1. 1 Barcelona Institute for Global Health (ISGlobal) Hospital Clínic, Universitat de Barcelona, Barcelona, Spain. 2. 2 National Institute of Health and Medical Research, U1047, Montpellier University, Nîmes, France. 3. 3 Department of Microbiology, University Hospital Nîmes, Nîmes, France. 4. 4 Microbiology Department, Hospital Universitari Bellvitge, Barcelona, Spain. 5. 5 Research Network for Respiratory Diseases (CIBERES), ISCIII, Madrid, Spain. 6. 6 Clinic Unit of Infectious Diseases, Microbiology and Preventive Medicine, Institute of Biomedicine of Seville, IBiS, University Hospital Virgen del Rocío/CSIC/University of Seville, Seville, Spain.
Abstract
Aim: This study analyzed the virulence of several Acinetobacter baumannii strains expressing different resistance mechanisms using the Caenorhabditis elegans infection model. Results: Strains susceptible/resistant to carbapenems (presenting class D (OXA-23, OXA-24), class B metallo-β-lactamase (MBL) (NDM-1), penicillin binding protein (PBP) altered and decreased expression of Omp 33-36 kDa) and isogenic A. baumannii strains susceptible/resistant to colistin (presenting loss of lipopolysaccharide (LPS) and pmrA mutations) were included to evaluate the virulence using the C. elegans infection model. The nematode killing assay, bacterial ingestion in worms, and bacterial lawn avoidance assay were performed with the Fer-15 mutant line. A. baumannii strains generally presented low virulence, showing no difference between carbapenem-resistant strains (expressing class D, MBLs, or altered PBP) and their isogenic susceptible strains. In contrast, the absence of the Omp 33-36 kDa protein in the knockout was associated with a decrease of virulence, and a significant difference was observed between colistin-resistant mutants and their susceptible counterpart when the mechanism of resistance was associated with the loss of LPS but not with its modification. Conclusions: Resistance to carbapenems in A. baumannii associated with the production of OXA-type or NDM-type enzymes does not seem to affect their virulence in the C. elegans infection model. In contrast, the presence of Omp 33-36 kDa, and high level resistance to colistin related with the loss of LPS, might contribute with the virulence profile in A. baumannii.
Aim: This study analyzed the virulence of several Acinetobacter baumannii strains expressing different resistance mechanisms using the Caenorhabditis elegans infection model. Results: Strains susceptible/resistant to carbapenems (presenting class D (OXA-23, OXA-24), class B metallo-β-lactamase (MBL) (NDM-1), penicillin binding protein (PBP) altered and decreased expression of Omp 33-36 kDa) and isogenic A. baumannii strains susceptible/resistant to colistin (presenting loss of lipopolysaccharide (LPS) and pmrA mutations) were included to evaluate the virulence using the C. elegansinfection model. The nematode killing assay, bacterial ingestion in worms, and bacterial lawn avoidance assay were performed with the Fer-15 mutant line. A. baumannii strains generally presented low virulence, showing no difference between carbapenem-resistant strains (expressing class D, MBLs, or altered PBP) and their isogenic susceptible strains. In contrast, the absence of the Omp 33-36 kDa protein in the knockout was associated with a decrease of virulence, and a significant difference was observed between colistin-resistant mutants and their susceptible counterpart when the mechanism of resistance was associated with the loss of LPS but not with its modification. Conclusions: Resistance to carbapenems in A. baumannii associated with the production of OXA-type or NDM-type enzymes does not seem to affect their virulence in the C. elegansinfection model. In contrast, the presence of Omp 33-36 kDa, and high level resistance to colistin related with the loss of LPS, might contribute with the virulence profile in A. baumannii.
Authors: Clara Cosgaya; Carlos Ratia; Marta Marí-Almirall; Laia Rubio; Paul G Higgins; Harald Seifert; Ignasi Roca; Jordi Vila Journal: Front Microbiol Date: 2019-10-24 Impact factor: 5.640
Authors: Liliana Scorzoni; Ana Carolina Alves de Paula E Silva; Haroldo Cesar de Oliveira; Claudia Tavares Dos Santos; Junya de Lacorte Singulani; Patricia Akemi Assato; Caroline Maria Marcos; Lariane Teodoro Oliveira; Nathália Ferreira Fregonezi; Diego Conrado Pereira Rossi; Leandro Buffoni Roque da Silva; Carlos Pelleschi Taborda; Ana Marisa Fusco-Almeida; Maria José Soares Mendes-Giannini Journal: J Fungi (Basel) Date: 2021-01-13
Authors: Hannah Valentino; David A Korasick; Tabbetha J Bohac; Justin A Shapiro; Timothy A Wencewicz; John J Tanner; Pablo Sobrado Journal: ACS Omega Date: 2021-07-06