Visualization of Germination Proteins in Putative Bacillus cereus Germinosomes

摘要: Bacillus cereus can survive in the form of spores for prolonged periods posing a serious problem manufacture safe shelf-stable foods optimal quality. Our study aims at increasing knowledge B. focusing primarily on germination mechanisms to develop novel milder food preservation strategies. Major features are core with genetic material encased by multiple protective layers, an important one being spores' inner membrane (IM), location many proteins. To involved spores, we have examined organization germinant receptors (GRs) IM. Previous studies indicated that ATCC 14579 L-alanine responsive GR, GerR, plays major role process. In our study, GerR GR subunit, GerRB, was as C-terminal SGFP2 fusion protein expressed under control gerR operon's promoter. results showed that: i) fluorescence maxima and integrated intensity plasmid-borne expression GerRB-SGFP2 were significantly higher than wild-type spores; ii) western blot analysis confirmed iii) microscopy visualized specific bright foci ~30% individual dormant if only expressed, but, noticeably, ~85% upon co-expression GerRA GerRC. data corroborates notion subunits improves their stability. Finally, all displayed fluorescent GerD-mScarlet-I gerD We termed observed germinosomes, term used IM GRs subtilis spores. first evidence existence germinosomes