From Dormant to Germinating Spores of Streptomyces coelicolor A3(2):  New Perspectives from the crp Null Mutant

Abstract

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.

Cell Wall Hydrolases Affect Germination, Vegetative Growth, and Sporulation in Streptomyces coelicolor

“…The RpfA and SwlA enzymes may act directly in degrading spore PG during germination or indirectly (for example, they may be involved in the formation of spore PG); in their absence, an altered substrate for germination-specific lytic enzymes may be generated, resulting in inefficient PG hydrolysis during germination. Germination defects have also been observed for crp mutants of S. coelicolor; however, these defects are thought to result, in part, from an abnormally thick spore wall, unlike the defect that we observed here (15,43).…”

The ROK Family Regulator Rok7B7 Pleiotropically Affects Xylose Utilization, Carbon Catabolite Repression, and Antibiotic Production in Streptomyces coelicolor

“…In Streptomyces, GlcNAc and fructose transport depend on the PTS, but glucose transport is mediated via the major facilitator superfamily (MFS) transporter GlcP (11). In terms of global regulation, streptomycetes lack a CcpA orthologue, while Crp is present but does not play a role in CCR (12). In contrast, in streptomycetes CCR largely depends on the enzyme glucose kinase (Glk; SCO2126), and deletion of the glkA gene results in global loss of CCR (13).…”

Transcription Activation Mediated by a Cyclic AMP Receptor Protein from Thermus thermophilus HB8

“…We found six CRP-cAMP-dependent promoters in in vitro transcription assays involving DNA fragments containing the upstream regions of the genes exhibiting de- Cyclic AMP (cAMP) receptor proteins (CRPs) are global transcriptional regulators broadly distributed in bacteria (30,72). The cellular roles of such CRP family proteins are diverse and include carbohydrate metabolism (3, 30), development of competence for transformation (8), modulation of virulence gene expression and pathogenesis (10,11,55,57,65), resuscitation (50), and germination and morphological development (13,49).Escherichia coli CRP controls the activity of over 100 genes and has been the most extensively studied so far (30, 72). This CRP was first named the catabolite gene-activating protein, since it induces the transcription of a number of genes in response to carbon source limitation (16,73).…”

“…The cellular roles of such CRP family proteins are diverse and include carbohydrate metabolism (3,30), development of competence for transformation (8), modulation of virulence gene expression and pathogenesis (10,11,55,57,65), resuscitation (50), and germination and morphological development (13,49).…”