title: Proteomic Analysis of Cellular and Membrane Proteins in Fluconazole-Resistant Candida glabrata.
abstract: OBJECTIVE
  Candida glabrata is one of the most common causes of Candida bloodstream infections worldwide. Some isolates of C glabrata may be intermediately resistant to azoles, with some strains developing resistance during therapy or prophylaxis with fluconazole. In this study, we used a proteomic approach to identify differentially expressed proteins between fluconazoleresistant and -susceptible strains.
  
  
  METHODS
  Membrane and cellular proteins were extracted from fluconazolesusceptible and fluconazole-resistant C glabrata strains. Differentially expressed proteins were compared using two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis. Proteins with >1.5-fold difference in expression were identified by liquid chromatography tandem mass spectrometry (LC-MS/MS).
  
  
  RESULTS
  A total of 65 proteins were differentially expressed in the cellular and membrane fractions. Among the 39 cellular proteins, 11 were upregulated and 28 were downregulated in fluconazole-resistant strains in comparison with fluconazole-susceptible strains. In the membrane fraction, a total of 26 proteins were found, of which 19 were upregulated and seven were downregulated. A total of 31 proteins were identified by LC-MS/MS that are involved in glycolysis, carbohydrate transport, energy transfer, and other metabolic pathways. Heat shock proteins were identified in various spots.
  
  
  CONCLUSIONS
  Heat shock and stress response proteins were upregulated in the membrane fraction of the fluconazole-resistant C glabrata strain. Compared with susceptible strains, fluconazole-resistant strains showed increased expression of membrane proteins and decreased expression of cellular proteins.
authors.affiliation: Division of Antimicrobial Resistance, Korea National Institute of Health, Osong, Korea.
authors.forename: Jae Il
authors.initials: JI
authors.lastname: Yoo
authors.forename: Chi Won
authors.initials: CW
authors.lastname: Choi
authors.forename: Hwa Su
authors.initials: HS
authors.lastname: Kim
authors.forename: Jung Sik
authors.initials: JS
authors.lastname: Yoo
authors.forename: Young Hee
authors.initials: YH
authors.lastname: Jeong
authors.forename: Yeong Seon
authors.initials: YS
authors.lastname: Lee
keywords: azole resistance; candidiasis; heat shock protein; proteomics; stress response protein