AterDDomain-Encoding Gene (SCO2368) Is Involved in Calcium Homeostasis and Participates in Calcium Regulation of a DosR-Like Regulon in Streptomyces coelicolor

Abstract

bAlthough Streptomyces coelicolor is not resistant to tellurite, it possesses several TerD domain-encoding (tdd) genes of unknown function. To elucidate the function of tdd8, the transcriptomes of S. coelicolor strain M145 and of a tdd8 deletion mutant derivative (the ⌬tdd8 strain) were compared. Several orthologs of Mycobacterium tuberculosis genes involved in dormancy survival were upregulated in the deletion mutant at the visual onset of prodiginine production. These genes are organized in a putative redox stress response cluster comprising two large loci. A binding motif similar to the dormancy survival regulator (DosR) binding site of M. tuberculosis has been identified in the upstream sequences of most genes in these loci. A predicted role for these genes in the redox stress response is supported by the low NAD ؉ /NADH ratio in the ⌬tdd8 strain. This S. coelicolor gene cluster was shown to be induced by hypoxia and NO stress. While the tdd8 deletion mutant (the ⌬tdd8 strain) was unable to maintain calcium homeostasis in a calcium-depleted medium, the addition of Ca 2؉ in ⌬tdd8 culture medium reduced the expression of several genes of the redox stress response cluster. The results shown in this work are consistent with Tdd8 playing a significant role in calcium homeostasis and redox stress adaptation.

Regulation of antibiotic production in Actinobacteria: new perspectives from the post-genomic era

“…Recently, it was shown that the DraRK TCS, which responds to high concentrations of nitrogen 113 , and the OsdRK TCS, which is oxygen6responsive, are similar in function to the system controlling dormancy in mycobacteria 112,120 , and are both required for Act production. Interestingly, in the absence of a functional DraRK system the production of…”

Translational control plays an important role in the adaptive heat-shock response of Streptomyces coelicolor

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“…Mycelia from the same bacterial cultures used in the polysome profiling experiments were treated with RNA Protect Bacteria Reagent and total RNA was extracted following a modified version of the method as described in 34 . In brief, the mycelia was harvest from four plates with a spatula and, after treatment with RNA protect Bacteria Reagent (Qiagen), was resuspended and lysed in 200 μ L Tris-EDTA plus Lysozyme (15mg/ml).…”

“…A total of five biological replicates were processed for transcriptome and translatome analysis. Each RNA sample (amount ranging from 2 to 10 μg depending on the availability) was labelled with Cy3dCTP using the method described in 34 .…”

OsdR of Streptomyces coelicolor and the Dormancy Regulator DevR of Mycobacterium tuberculosis Control Overlapping Regulons

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