Comprehensive proteomic profiling of outer membrane vesicles from Campylobacter jejuni
Gram-negative bacteria constitutively release outer membrane vesicles (OMVs) during cell growth that play significant roles in bacterial survival, virulence and pathogenesis. In this study, comprehensive proteomic analysis of OMVs from a human gastrointestinal pathogen Campylobacter jejuni NCTC11168 was performed using high-resolution mass spectrometry. The OMVs of C. jejuni NCTC11168 were isolated from culture supernatants then characterized using electron microscopy and dynamic light scattering revealing spherical OMVs of an average diameter of 50 nm. We then identified 134 vesicular proteins using high-resolution LTQ-Orbitrap mass spectrometry. Subsequent functional analysis of the genes revealed the relationships of the vesicular proteins. Furthermore, known N-glycoproteins were identified from the list of the vesicular proteome, implying the potential role of the OMVs as a delivery means for biologically relevant bacterial glycoproteins. These results enabled us to elucidate the overall proteome profile of pathogenic bacterium C. jejuni and to speculate on the function of OMVs in bacterial infections and communication.
© 2013 Elsevier B.V. Received 12 April 2013; Accepted 17 December 2013; Available online 29 December 2013. We thank Sarkis Mazmanian for providing support for bacterial culture growth, Alasdair McDowall in the Cryo-electron Microscopy Facility at the Broad Center for the help with electron microscopy, and Axel Müller for optimizing the bacterial growth conditions (all at Caltech). We also thank V. Somalinga and A. Müller for their critical reading of our paper. This work was supported by a Searle Scholar Fellowship and a Burroughs-Wellcome Fund Career Award to WMC. The PEL is supported by the Gordon and Betty Moore Foundation through Grant 442 GBMF775 and the Beckman Institute.
Supplemental Material - Jang_2014p90_si.pdf
Accepted Version - nihms713356.pdf