The clpP multigenic family in Streptomyces lividans: conditional expression of the clpP3 clpP4 operon is controlled by PopR, a novel transcriptional activator

Julie Viala (1) , Georges Rapoport (1) , Philippe Mazodier (1)

1 Biochimie Microbienne

The clpP genes are widespread among living organisms and encode the proteolytic subunit of the Clp ATP-dependent protease. These genes are present in a single copy in most eubacteria. However, five clpP genes were identified in Streptomyces coelicolor. The clpP1 clpP2 operon was studied: mutations affected the growth cycle in various Streptomyces. Here, we report studies of the expression of the clpP3 clpP4 operon in Streptomyces lividans. The clpP3 operon was induced in a clpP1 mutant strain, and the regulation of expression was investigated in detail. The product of the putative regulator gene, downstream from clpP4, was purified. Gel migration shift assays and DNase I footprinting showed that this protein binds to the clpP3 promoter and recognizes a tandem 6 bp palindromic repeat (TCTGCC-3N-GGCAGA). In vivo, this DNA-binding protein, named PopR, acts as an activator of the clpP3 operon. Studies of popR expression indicate that the regulator is probably controlled at the post-transcriptional level.

Domaines: Biochimie, Biologie Moléculaire

Julie Viala, Georges Rapoport, Philippe Mazodier. The clpP multigenic family in Streptomyces lividans: conditional expression of the clpP3 clpP4 operon is controlled by PopR, a novel transcriptional activator. Molecular Microbiology, 2000, 38 (3), pp.602-612. ⟨10.1046/j.1365-2958.2000.02155.x⟩. ⟨hal-03269528⟩