title: Association of the outer membrane protein Omp33 with fitness and virulence of Acinetobacter baumannii.
abstract: Outer membrane protein 33 (Omp33) is an outer membrane porin of Acinetobacter baumannii associated with carbapenem resistance. However, the role of Omp33 in the fitness and virulence of A. baumannii remains unknown. In the present study, we investigated the role of Omp33 in fitness and virulence of A. baumannii by using an isogenic knockout strain deficient in the omp33 gene (JPAB02), derived from the ATCC 17978 wild-type (wt). Both in vitro and in vivo defect in the growth rate was found in the JPAB02 strain in competition with the ATCC 17978 wt, highlighting the effect of Omp33 on the metabolic fitness. A significant reduction was observed both in adherence and invasion of human lung epithelial cells and in cytotoxicity of these cells and macrophages with JPAB02. In a murine peritoneal sepsis model, the JPAB02 strain exhibited lower lethal dose 0 (LD0), LD50, and LD100, and dissemination in mice, with reduced bacterial concentration in spleen and lungs. From these data, we concluded that Omp33 plays an important role for fitness and virulence of A. baumannii.
authors.affiliation: Clinic Unit of Infectious Diseases, Microbiology and Preventive Medicine, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío/CSIC/University of Seville, Spain.
authors.forename: Younes
authors.initials: Y
authors.lastname: Smani
authors.forename: Juan
authors.initials: J
authors.lastname: Dominguez-Herrera
authors.forename: Jerónimo
authors.initials: J
authors.lastname: Pachón
mesh_terms: D000151:Acinetobacter Infections / Q000382:microbiology / Q000401:mortality; D040981:Acinetobacter baumannii / Q000235:genetics* / Q000254:growth & development / Q000472:pathogenicity*; D000818:Animals; D001422:Bacterial Adhesion / Q000235:genetics; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D018441:Biofilms; D016923:Cell Death; D002460:Cell Line; D004195:Disease Models, Animal; D004847:Epithelial Cells / Q000378:metabolism / Q000382:microbiology; D055786:Gene Knockout Techniques; D056084:Genetic Fitness; D006801:Humans; D051379:Mice; D010538:Peritonitis / Q000382:microbiology / Q000401:mortality; D010641:Phenotype; D014774:Virulence / Q000235:genetics
chemical_list: D001425:Bacterial Outer Membrane Proteins
keywords: Acinetobacter baumannii; Omp33; fitness; virulence