Isolation and identification of Enterococcus faecalis membrane proteins using membrane shaving, 1D SDS/PAGE, and mass

Peter Cathro1, Peter McCarthy2, Peter Hoffmann3

  • 1Oral Microbiology Laboratory School of Dentistry The University of Adelaide South Australia Australia.

FEBS Open Bio
|July 16, 2016
PubMed

Insights

This study identifies 222 membrane proteins in Enterococcus faecalis, a common hospital pathogen. The novel combined method enhances understanding of bacterial adaptation and antimicrobial resistance mechanisms.

Area of Science:

  • Microbiology
  • Proteomics
  • Bacterial Pathogenesis

Background:

  • Enterococcus faecalis is a significant nosocomial pathogen known for environmental adaptability and antimicrobial resistance.
  • Cell membrane proteins are crucial for bacterial stress response and survival.
  • Understanding E. faecalis membrane proteome is key to deciphering its survival strategies.

Purpose of the Study:

  • To develop and apply a combined proteomic approach for identifying membrane proteins in E. faecalis.
  • To characterize the identified membrane proteins and their functions.
  • To establish protocols for future studies on E. faecalis membrane proteome dynamics.

Main Methods:

  • Fractionation of E. faecalis ATCC V583 membranes using 1D SDS/PAGE and membrane shaving.
  • Analysis of fractionated samples using Liquid Chromatography-Electrospray Ionization mass spectrometry (LC-ESI-MS).
  • Identification and quantification of membrane-associated proteins.

Main Results:

  • Identification of 222 membrane-associated proteins, representing approximately 24% of the predicted proteome.
  • 170 proteins identified via 1D SDS/PAGE, 68 via membrane shaving, with 36 common to both.
  • Membrane shaving yielded high-purity membrane proteins (97%), predominantly integral membrane proteins (89%).
  • Identified proteins are largely involved in transmembrane transport.

Conclusions:

  • The combined 1D SDS/PAGE and membrane shaving approach is highly effective for comprehensive membrane proteome analysis in E. faecalis.
  • This study provides the most extensive list of identified membrane proteins in E. faecalis to date.
  • The developed protocols will facilitate future research into E. faecalis adaptation and response to environmental challenges and antimicrobial therapies.