Identified members of the Streptomyces lividans AdpA regulon involved in differentiation and secondary metabolism.
BACKGROUND
AdpA is a key transcriptional regulator involved in the complex growth cycle of Streptomyces. Streptomyces are Gram-positive bacteria well-known for their production of secondary metabolites and antibiotics. Most work on AdpA has been in S. griseus, and little is known about the pathways it controls in other Streptomyces spp. We recently discovered interplay between ClpP peptidases and AdpA in S. lividans. Here, we report the identification of genes directly regulated by AdpA in S. lividans.


RESULTS
Microarray experiments revealed that the expression of hundreds of genes was affected in a S. lividans adpA mutant during early stationary phase cultures in YEME liquid medium. We studied the expression of the S. lividans AdpA-regulated genes by quantitative real-time PCR analysis after various times of growth. In silico analysis revealed the presence of potential AdpA-binding sites upstream from these genes; electrophoretic mobility shift assays indicated that AdpA binds directly to their promoter regions. This work identifies new pathways directly controlled by AdpA and that are involved in S. lividans development (ramR, SLI7885 also known as hyaS and SLI6586), and primary (SLI0755-SLI0754 encoding CYP105D5 and Fdx4) or secondary (cchA, cchB, and hyaS) metabolism.


CONCLUSIONS
We characterised six S. lividans AdpA-dependent genes whose expression is directly activated by this pleiotropic regulator. Several of these genes are orthologous to bldA-dependent genes in S. coelicolor. Furthermore, in silico analysis suggests that over hundred genes may be directly activated or repressed by S. lividans AdpA, although few have been described as being part of any Streptomyces AdpA regulons. This study increases the number of known AdpA-regulated pathways in Streptomyces spp.
Aurélie
A
Guyet
Nadia
N
Benaroudj
Caroline
C
Proux
Myriam
M
Gominet
Jean-Yves
JY
Coppée
Unité de Biologie des Bactéries Pathogènes à Gram-Positif, Institut Pasteur, CNRS URA 2172, 28 rue du Docteur Roux, 75724 Paris Cedex 15, France. philippe.mazodier@pasteur.fr.
Philippe
P
Mazodier
D001665:Binding Sites; D019295:Computational Biology; D003470:Culture Media / Q000737:chemistry; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D046228:Microarray Analysis; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D060888:Real-Time Polymerase Chain Reaction; D018085:Regulon; D064210:Secondary Metabolism; D048170:Streptomyces lividans / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D013997:Time Factors; D015534:Trans-Activators / Q000378:metabolism*
D003470:Culture Media; D004269:DNA, Bacterial; D015534:Trans-Activators