Synthesis of ribosomal proteins during growth of Streptomyces coelicolor

Abstract

Changes in expression of ribosomal protein genes during growth and stationary phase of Streptomyces coelicolor A3(2) in liquid medium were studied. Proteins being synthesized were pulse-labelled with [35S]-methionine, separated by two-dimensional polyacrylamide gel electrophoresis, and quantified using the BioImage computer software. Most of the ribosomal proteins were synthesized throughout the life cycle. Exceptions were two proteins whose synthesis drastically decreased at the approach of stationary phase. These two proteins were identified in purified ribosomes as homologues of Escherichia coli ribosomal proteins L10 and L7/L12, using antibodies raised against fusion proteins between these ribosomal proteins and Escherichia coli beta-galactosidase. The genes (rplJ and rplL) encoding the L10 and L7/L12 proteins were contained in a 1.2 kb BamHI fragment that was cloned and sequenced. The linkage and order of the genes coincide with other L10-L7/L12 operons. However, L11 and L1 genes were not present immediately upstream of the L10 gene, as is the case for E. coli and other bacteria. Instead, two open reading frames of unknown function were found immediately upstream of the L10 gene, in an adjacent 1.9 kb BamHI fragment.

Mycelium Differentiation and Antibiotic Production in Submerged Cultures ofStreptomyces coelicolor

“…This growth arrest precedes antibiotic production (28) and can activate antibiotic biosynthetic genes (31,43), antibiotic resistance genes (50), and stress response stimulons (48), as well as arrest of ribosomal protein synthesis (3). In this work, we demonstrate that this growth arrest corresponds to the transition phase from the first vegetative compartmentalized mycelium to the second multinucleated differentiated mycelium, which is the one which produces antibiotics.…”

Predicted highly expressed genes in the genomes of Streptomyces coelicolor and Streptomyces avermitilis and the implications for their metabolism

“…1), suggesting that considerable heterogeneity is present in these GC-rich genomes. The genes encoding ribosomal proteins, which are expected to be expressed at high levels during rapid cell growth in Streptomyces (Blanco et al, 1994), were identified and are highlighted in the N c plots. The clustering of most of the ribosomal protein genes of the two Streptomyces genomes at low ends is similar to that in the GC3s versus N c plot of the E. coli genome (data not shown).…”

Cloning, sequencing and transcriptional analysis of a Streptomyces coelicolor operon containing the rplM and rpsI genes encoding ribosomal proteins ScoL13 and ScoS9

“…Important aspects of primary metabolism, such as the machinery involved in protein synthesis, have not been studied in such great detail. Dierences in the ribosomal protein pattern among several streptomycete species have been described (Fierro et al 1987;Ochi 1992) and changes in the pattern of ribosomal proteins during spore germination (Mikulik et al 1984;Quiro s et al 1989) and during the transition from substrate to aerial mycelium (Quiro s et al 1992;Blanco et al 1994) have also been noted. Only a few genes encoding Streptomyces ribosomal proteins have been cloned and sequenced and they correspond to only a few operons: the L11 and L10 operons (Blanco et al 1992(Blanco et al , 1994Parra et al 1992;Ruengjitchawalya et al 1993;Katayama et al 1996), the L34 operon (Calcutt and Schmidt 1992), the spc operon (Hale et al 1995) and the alpha operon (Cho et al 1996).…”