A Novel Lipid-Based MALDI-TOF Assay for the Rapid Detection of Colistin-Resistant Enterobacter Species

Richard D. Smith, Christi L. McElheny, Jerilyn R. Izac, Francesca M. Gardner, Courtney E. Chandler, David R. Goodlett, Yohei Doi, J. Kristie Johnson, Robert K. Ernst

研究成果: ジャーナルへの寄稿学術論文査読

6 被引用数 (Scopus)


Enterobacter species are classified as high-priority pathogens due to high prevalence of multidrug resistance from persistent antibiotic use. For Enterobacter infections caused by multidrug-resistant isolates, colistin (polymyxin E), a last-resort antibiotic, is a potential treatment option. Treatment with colistin has been shown to lead to emergence of polymyxin resistance. The primary mechanism for colistin resistance is modification of terminal phosphate moieties of lipid A, leading to decreased membrane electronegativity and reducing colistin binding affinity. Detection of these modifications, including the addition of phosphoethanolamine and 4-amino-4-deoxy-Larabinose (Ara4N), can be used for prediction of colistin resistance using matrixassisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The objective of this study was to identify lipid A markers for colistin resistance in Enterobacter species and Klebsiella aerogenes (formerly Enterobacter aerogenes). Using a collection of Enterobacter and Klebsiella aerogenes clinical isolates, broth MICs for colistin were determined initially. Subsequently, killing assays were carried out to determine how the concentration of colistin at which there is approximately 50% survival (kill50) equates to their MICs. Finally, lipid A analysis was conducted via MALDI-TOF MS using the novel rapid extraction method, termed fast lipid analysis technique (FLAT), to correlate MIC and killing efficacy with predictive lipid A modifications. Sensitivity and specificity of the MS assay compared to MIC interpretation were 100% and 53.4%, respectively. A receiver operator characteristic (ROC) demonstrated that MS was highly correlated with killing, with area under the curve of 0.97. This analysis demonstrated the potential utility of MALDI-TOF MS as a rapid diagnostic platform of colistin resistance in Enterobacter species.

ジャーナルMicrobiology spectrum
出版ステータス出版済み - 02-2022

All Science Journal Classification (ASJC) codes

  • 生理学
  • 生態学
  • 免疫学および微生物学(全般)
  • 遺伝学
  • 微生物学(医療)
  • 細胞生物学
  • 感染症


「A Novel Lipid-Based MALDI-TOF Assay for the Rapid Detection of Colistin-Resistant Enterobacter Species」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。