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

Abstract

The N-terminal amino acid sequences of two peptides derived from a Streptomyces coelicolor ribosomal protein were determined and degenerate oligonucleotide primers derived from these sequences were used as probes for the screening of a chromosomal DNA library of S. coelicolor. Two positive clones were isolated and DNA sequencing of a 1740-bp region of these clones that hybridised with the probes revealed the presence of four genes, two of them incomplete. The deduced products of the two complete genes. rplM and rpsI, showed clear similarities to L13 and S9 ribosomal proteins from various organisms. Promoter-probe and primer extension experiments suggest that the two genes form a single transcriptional unit. The specific rate of synthesis of both proteins was high at early stages of growth but decreased later.

Cloning of therplAgene encoding ribosomal protein L1 fromStreptomyces aureofaciensand its transcriptional analysis in the course of differentiation

“…On the contrary, the expression of all ribosomal proteins, as measured by protein pulse‐labelling experiments in S. coelicolor , decreased along the cell cycle in liquid‐grown culture and the synthesis of at least two ribosomal proteins (L7/L12 and L10) stopped after 20–24 h of growth [3]. A similar decrease of expression along the cell cycle was found for the operon containing rplM and rpsI genes encoding ribosomal proteins ScoL13 and ScoS9 in S. coelicolor [5]. However, all these studies were performed with the liquid‐grown cells and there are no data about the expression of ribosomal protein genes in Streptomyces at the different developmental stages during the morphological differentiation in solid‐grown cultures.…”

“…Several genes encoding Streptomyces ribosomal proteins have been cloned and sequenced. They comprise the rplJL operon encoding ribosomal protein L7/L12 in Streptomyces antibioticus [4] and in S. coelicolor [3], the rplM, rpsI operon encoding L13, S9 in S. coelicolor [5], the rplKA and rplJL operons encoding L11, L1 and L7/12, L10, respectively, in Streptomyces griseus [6]. However, the transcriptional analysis has only been performed in the rplM, rpsI operon in S. coelicolor [5] and with rplKA and rplJL operons in S. griseus [6].…”