Pleiotropic role of the Sco1/SenC family copper chaperone in the physiology of Streptomyces.
Bottom Line: The scoC mutant of S. griseus was also defective in the extracellular activity oxidizing N,N'-dimethyl-p-phenylenediamine sulfate.Addition of 10 µM CuSO(4) repressed the activity of the conserved promoter preceding scoA and caused phenylalanine auxotrophy in some Streptomyces spp. probably because of the repression of pheA; pheA encodes prephenate dehydratase, which is located at the 3' terminus of the putative operon structure.Overall, the evidence indicates that Sco is crucial for the utilization of copper under a low-copper condition and for the activation of the multiple Cu(2+) -containing oxidases that play divergent roles in the complex physiology of Streptomyces.
Affiliation: Life Science Research Center, College of Bioresource Sciences, Nihon University, 1866 Kameino, Fujisawa, Japan.Show MeSH
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Mentions: Figure 1A schematically represents the gene organization of the sco (Streptomyces copper utilization) locus. The results of sequence similarity (blast) and motif (MOTIF) searches as well as the annotation supplied in the genomic database (http://www.genome.jp/) indicated that the gene cluster consists of seven unidirectional coding sequences encoding the following proteins (the amino acid numbers in parentheses are those for S. coelicolor proteins): ScoA (284 aa), an integral membrane protein; ScoB (253 aa), a hypothetical protein containing the eukaryotic lysine‐oxoglutarate reductase/saccharopine dehydrogenase (LOR/SDH) bifunctional enzyme conserved region; ScoC (216 aa), an Sco1/SenC‐like protein containing a 1–16 aa N‐terminal prokaryotic membrane lipoprotein lipid attachment site; ScoD (178 aa), a hypothetical protein; ScoE (680 aa), a membrane‐associating protein containing an N‐terminal prokaryotic membrane lipoprotein lipid attachment site (1–21 aa) and CopC‐ (13–128 aa) and CopD‐like (341–420, 498–540 aa) domains; ScoF (445 aa), a secreted protein containing the Tat (twin arginine translocation) signal peptide (1–64 aa) and the 87–433‐aa Dyp (dye‐decolorizing peroxidase)‐type peroxidase domain; and PheA (310 aa), prephenate dehydratase involved in phenylalanine biosynthesis. It appears likely that most Sco proteins are membrane‐associated. The tandem localization of these seven coding sequences is conserved in all the genome‐sequenced Streptomyces spp. (Fig. 1A).
Affiliation: Life Science Research Center, College of Bioresource Sciences, Nihon University, 1866 Kameino, Fujisawa, Japan.