C. difficile strain 630 flagellin C modifications

ABSTRACT: In proteomics, the study of post-translational modifications often relies on some type of enrichment strategy. Here, we show that an approach that is commonly used in phosphoproteomics (Immobilised Metal Affinity Chromatography (Fe3+-IMAC)) also enriches for peptides with a unique post-translational modification, known as type A, in the human pathogen Clostridioides difficile. The type A modification consists of a monosaccharide (GlcNAc) that is linked to an N-methylated threonine through a phosphodiester bond. This structure has previously been described on flagellin C of several C. difficile strains and is important for bacterial motility. Using LC-MS/MS analyses of IMAC-captured tryptic peptides, we not only observed Type A modified C. difficile flagellin peptides but also a variety of truncated/modified Type A structures on these peptides. Using an elaborate set of mass spectrometry analyses, we demonstrate that one of these modifications consists of a Type A structure containing a phosphonate (2-aminoethylphosphonate, 2-AEP), a modification that is rarely observed and has hitherto not been described in C. difficile.

INSTRUMENT(S):

ORGANISM(S): Peptoclostridium Difficile (strain 630) (clostridium Difficile)

SUBMITTER: Yassene Mohammed  

LAB HEAD: Paul J. Hensbergen

PROVIDER: PXD029552 | Pride | 2022-04-04

REPOSITORIES: Pride