Quantitative proteomic analysis of Shigella flexneri and Shigella sonnei Generalized Modules for Membrane Antigens (GMMA) reveals highly pure preparations.

ABSTRACT: Shigella flexneri 2a and Shigella sonnei were genetically modified to shed large quantities of outer membrane blebs. The blebs, called Generalized Modules for Membrane Antigens (GMMA), were purified and the protein content was estimated using the label-free iBAQ procedure. There were 2308 proteins identified, 660 in GMMA and 2239 in bacteria, of which 288 (GMMA) and 1695 (bacteria) were common to both S. flexneri 2a and S. sonnei. Protein abundances were classified according to the predicted localization. Predicted outer membrane or periplasmic proteins constituted 95.7% and 98.7% of the protein mass of S. flexneri 2a and S. sonnei GMMA, respectively. Among the remaining proteins, small quantities of ribosomal proteins collectively accounted for more than half of the predicted cytoplasmic protein impurities in the GMMA. In GMMA, the outer membrane and periplasmic proteins were enriched 13.3-fold (S. flexneri 2a) and 8.3-fold (S. sonnei) compared to their abundance in the parent bacteria. Both periplasmic and outer membrane proteins were enriched similarly, suggesting that GMMA have a similar surface to volume ratio as the surface to periplasmic volume ratio in these mutant bacteria. Results in S. flexneri 2a and S. sonnei showed high reproducibility indicating a robust GMMA-producing process.

INSTRUMENT(S): LTQ Orbitrap Velos

ORGANISM(S): Shigella Flexneri 2a Str. 2457t Shigella Sonnei 53g

SUBMITTER: James Wright  

LAB HEAD: Jyoti Choudhary

PROVIDER: PXD002517 | Pride | 2016-01-12

REPOSITORIES: Pride