A protease for 'middle-down' proteomics

Nat Methods. 2012 Jun 17;9(8):822-4. doi: 10.1038/nmeth.2074.

Abstract

We developed a method for restricted enzymatic proteolysis using the outer membrane protease T (OmpT) to produce large peptides (>6.3 kDa on average) for mass spectrometry-based proteomics. Using this approach to analyze prefractionated high-mass HeLa proteins, we identified 3,697 unique peptides from 1,038 proteins. We demonstrated the ability of large OmpT peptides to differentiate closely related protein isoforms and to enable the detection of many post-translational modifications.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • HeLa Cells
  • Humans
  • Mass Spectrometry
  • Peptides / analysis*
  • Peptides / chemistry
  • Peptides / metabolism*
  • Protein Isoforms / chemistry
  • Protein Isoforms / metabolism
  • Protein Processing, Post-Translational
  • Proteolysis*
  • Proteomics / methods*
  • Serine Endopeptidases / chemistry
  • Serine Endopeptidases / metabolism*

Substances

  • Peptides
  • Protein Isoforms
  • Serine Endopeptidases
  • omptin outer membrane protease