Colistin resistance associated with outer membrane protein change in Klebsiella pneumoniae and Enterobacter asburiae

Abstract

In this study, outer membrane proteins (OMPs) of colistin-resistant Klebsiella pneumoniae and Enterobacter asburiae were analyzed. One colistin-susceptible and three colistin-resistant K. pneumoniae sequence type 258 strains as well as one colistin-susceptible E. asburiae and its colistin-heteroresistant counterpart strain were involved in the study. OMP analysis of each strain was performed by microchip method. Matrix-assisted laser desorption ionization time of flight/mass spectrometry (MALDI-TOF/MS) investigation was carried out after separation of OMPs by two-dimensional gel electrophoresis and in-gel digestion. The MALDI-TOF/MS analysis of OMPs in the colistin-susceptible K. pneumoniae found 16 kDa proteins belonging to the LysM domain/BON superfamily, as well as DNA starvation proteins, whereas OmpX and OmpW were detected in the colistin-resistant counterpart strains. OmpC and OmpW were detected in the colistin-susceptible E. asburiae, whereas OmpA and OmpX were identified in the colistin-resistant counterpart. This study demonstrated that OMP differences were between colistin-susceptible and -resistant counterpart strains. The altered Gram-negative cell wall may contribute to acquired colistin resistance in Enterobacteriaceae.

Emergence of Colistin Resistance in Carbapenem-Resistant Hypervirulent Klebsiella pneumoniae Under the Pressure of Tigecycline

“…Other efflux pumps, including KpnEF, along with alterations in the LPS and outer membrane proteins mediated by changes in the ramA and omp genes have also been reported to decrease susceptibility to colistin ( Srinivasan and Rajamohan, 2013 ; De Majumdar et al, 2015 ; Kádár et al, 2017 ). However, we found no mutations in KpnEF in our strains.…”

KPC-2-producing Klebsiella pneumoniae ST147 in a neonatal unit: Clonal isolates with differences in colistin susceptibility attributed to AcrAB-TolC pump

“…Additionally, resistance to colistin is also attributed to change in porin profile among Enterobacteriaceae [39]. All the isolates showed similar pattern of porins, loss of OmpK35 but intact OmpK36.…”

Polymyxins and Bacterial Membranes: A Review of Antibacterial Activity and Mechanisms of Resistance

“…Furthermore, OmpC and OmpW were detected in the colistin-susceptible E. asburiae , whereas OmpA and OmpX were identified in the colistin-resistant counterpart. This demonstrated that the altered Gram-negative cell wall may contribute to acquired colistin resistance in Enterobacteriaceae [ 119 ]. Another study investigated the influence of lipid A acylation pattern on the crucial interaction between the LPS of a clinical K. pneumoniae isolate and polymyxins.…”