In vitro pathogenicity analysis of carbapenem-resistant Enterobacter spp.
10.13602/j.cnki.jcls.2025.09.03
- VernacularTitle:耐碳青霉烯类肠杆菌属的体外致病性分析
- Author:
Mei HAN
1
;
Jun JI
;
Jun LUO
;
Han SHEN
;
Xiaoli CAO
;
Chang LIU
Author Information
1. 南京大学医学院附属鼓楼医院检验科,南京 210008
- Publication Type:Journal Article
- Keywords:
carbapenem-resistant Enterobacter spp.;
growth in vitro;
biofilm;
serum bactericidal assays;
Galleria mellonella infection model;
pathogenicity
- From:
Chinese Journal of Clinical Laboratory Science
2025;43(9):649-654
- CountryChina
- Language:Chinese
-
Abstract:
Objective To analyze the interspecies differences in virulence of different carbapenem-resistant Enterobacterales(CREb)strains and provide a theoretical basis for understanding the pathogenic mechanisms of CREb and for guiding individualized treatment strategies.Methods A total of nine CREb clinical isolates collected between 2013 and 2022 were included,representing five species:Enterobacter cloacae(E.cloacae),Enterobacter hormaechei(E.hormaechei),Enterobacter kobei(E.kobei),Enterobacter asburiae(E.asburiae),and Enterobacter chuandaensis(E.chuandaensis).Whole-genome sequencing was performed to characterize virulence gene profiles.Phenotypic assays included growth curve analysis,biofilm formation assessment,serum bactericidal assays,and Galleria mellonella infection models to evaluate virulence-related traits.Results Virulence gene analysis revealed that motility-related factors were the most abundant(16 to 20 per strain),followed by nutrition/metabolism-related factors(10 to 12 per strain),while invasion-related genes were rare,with the ibeB gene detected in only two E.asburiae strains.The strains of the same species shared similar viru-lence gene profiles,and E.chuandaensis harbored the fewest virulence genes.In vitro growth assays showed that E.hormaechei and E.cloacae had the fastest growth rates,while E.chuandaensis and E.kobei exhibited slower growth,and E.asburiae displayed the slo-west growth.Biofilm assays indicated that E.hormaechei and E.cloacae had the strongest biofilm-forming capacity,while E.kobei had the weakest.In serum bactericidal assays,E.hormaechei and E.cloacae showed high survival rates(＞70%),whereas the survival rate of E.chuandaensis was less than 1%.In the Galleria mellonella model,E.asburiae and E.cloacae exhibited marked dose-dependent virulence,whereas the remaining strains showed reduced virulence.Conclusion Different CREb species exhibit significant variation in virulence gene content and phenotypic traits.The pathogenic potential of CREb may provide fundamental data to inform strategies for prevention and treatment of CREb infection.
