From dormant to germinating spores of Streptomyces coelicolor A3(2): new perspectives from the crp null mutant

The complete understanding of the morphological differentiation of streptomycetes is an ambitious challenge as diverse sensors and pathways sensitive to various environmental stimuli control the process. Germination occupies a particular position in the life cycle as the good achievement of the process depends on events occurring both during the preceding sporulation and during germination per se. The cyclic AMP receptor protein (crp) null mutant of Streptomyces coelicolor, affected in both sporulation and germination, was therefore presented as a privileged candidate to highlight new proteins involved in the shift from dormant to germinating spores. Our multidisciplinary approach-combining in vivo data, the analysis of spores morphological properties, and a proteome study-has shown that Crp is a central regulatory protein of the life cycle in S. coelicolor; and has identified spores proteins with statistically significant increased or decreased expression that should be listed as priority targets for further investigations on proteins that trigger both ends of the life cycle.