The role of the Cronobacter sakazakii ProP C-terminal coiled coil domain in osmotolerance

BACKGROUND: We investigate the role of the C-terminal coiled coil of the secondary proline porter ProP in contributing to Cronobacter sakazakii osmotolerance. FINDINGS: The extended C-terminal domain of ProP1 (encoded by ESA_02131) was spliced onto the truncated C-terminal end of ProP2 (encoded by ESA_01706); creating a chimeric protein (ProPc) which exhibits increased osmotolerance relative to the wild type. CONCLUSIONS: It appears that the C-terminal coiled coil domain tunes ProP at low osmolality, whereas ProP transporters lacking the coiled coil domain are more active at a higher osmolality range.