0000000000768441
AUTHOR
C. Vocat
THE SMALL PROTEIN SCO2038 CONTROLS TRYPTOPHAN BIOSYNTHESIS AND DIFFERENTIATION IN STREPTOMYCES COELICOLOR
The cellular regulatory factors comprise regulatory proteins, small RNA and small proteins. It is known that the product of small orfs (smorfs) can regulate the translation of downstream elements and also can encode functional peptides involved in the regulation of specific pathways (Ladoukakis E. et al.,2011). In particular, in the model streptomycete Sfreptomyces coelicolor, smorfs (about 100-300 nucleotides) were identified in some amino acid biosynthetic gene clusters such as in the tryptophan trpCXBA locus (Limauro D. et al., I 990; Hu DS. et al., 1999). In S. coelicolor the molecular mechanisms that regulate tryptophan (Trp) biosynthesis are poorly understood and, unlike the trp opero…
The small protein SCO2038 controls Streptomyces coelicolor differentiation by modulating tryptophan biosynthesis
Background In Streptomyces coelicolor amino acid metabolism is an important clue of the morphological and physiological differentiation program and, differently from other bacteria, the expression of amino acid biosynthetic genes is not subjected to endproduct negative regulation. In some amino acid biosynthetic gene clusters, such as tryptophan, histidine and proline, small orfs (about 100-300 nucleotides) were identified. These small orfs, such as sco2038, encode proteins whose cellular role have to be elucidated to highlight possible novel and crucial molecular mechanisms controlling amino acid synthesis and, thus, differentiation program. Objectives The aims of this work are: 1. the und…
The small protein SCO2038 modulates tryptophan biosynthesis and morpho-physiological differentiation in Streptomyces coelicolor
In Streptomyces coelicolor small open reading frames were identified in several amino acids biosynthetic gene clusters, like SCO2038 (trpX) in the tryptophan trpCXBA locus. Here, the role of SCO2038, encoding a 63 amino acid protein, was investigated by both phenotypic and molecular analyses. A SCO2038 knockout mutant strain showed a delayed growth on minimal medium (MM), compromised actinorhodin biosynthesis and poor sporulation. The capability of this mutant to grow on MM was restored by tryptophan’s and its precursors’ supplementation. Pulldown and bacterial two hybrid assays revealed SCO2038 interaction with PepA, which is putatively involved in the metabolism of serine, glycine and cys…