New two-component regulatory system required for the constitutive expression of bph operon in Cupriavidus basilensis WS
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Cupriavidus basilensis WS degrades diphenyl ether (DE) and its lower brominated derivatives using enzymes encoded by the bph operon. However, it is not yet known under what circumstances bph genes are expressed and how they are regulated in C. basilensis WS. To answer these questions, we used transposon mutagenesis and identified a new two-component regulatory system, BphS/BphT, in C. basilensis WS, which is indispensable for the expression of the bph operon. When BphS or BphT is inactivated, C. basilensis WS no longer exhibits the ability to decompose DE. Using a β-galactosidase reporter system and RT-qPCR, we showed that bph genes are constitutively transcribed in C. basilensis WS and that deletion of bphS or bphT strongly inhibited the transcription of bph genes. We also showed that the gene ORF0, which is upstream of bphA1 and is similar to the GntR-family regulators of the bph operon, is not involved in the constitutive transcription of the bph operon in C. basilensis WS. The cis-acting elements required for the expression and regulation of bph genes in the DE degradation pathway are included in the intergenic region between ORF0 and bphA1. Our results suggest that BphS/BphT represents a new two-component regulatory system for the bph operon that is necessary for the constitutive expression of bph genes.
Keywordsbph operon Transcription Two-component regulatory system Diphenyl ether
This study was supported by the National Key Basic Research Program of China (2015CB150502), the National Natural Science Foundation of China (31470191, 41671314, 41877114), the Zhejiang Provincial Natural Science Foundation of China (LQ17D010001), and the Key Research and Development Program of Zhejiang Province (2015C03011).
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Conflict of interest
The authors declare they have no conflict of interest.
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This article does not contain any studies with human participants performed by any of the authors.
- Breland EJ, Eberly AR, Hadjifrangiskou M (2017) An Overview of Two-Component Signal Transduction Systems Implicated in Extra-Intestinal Pathogenic E-coli Infections. Front Cell Infect Microbiol 7:–162Google Scholar
- Fortnagel P, Harms H, Wittich R-M, Krohn S, Meyer H, Sinnwell V, Wilkes H, Francke W (1990) Metabolism of dibenzofuran by Pseudomonas sp. strain HH69 and the mixed culture HH27. Appl Environ Microbiol 56(4):1148–1156Google Scholar
- Hamblin MJ, Shaw JG, Kelly DJ (1993) Sequence analysis and interposon mutagenesis of a sensor-kinase (DctS) and response-regulator (DctR) controlling synthesis of the high-affinity C4-dicarboxylate transport system in Rhodobacter capsulatus. Mol Gen Genet 237(1–2):215–224Google Scholar
- Liu Q, Yeo WS, Bae T (2016) The SaeRS two-component system of Staphylococcus aureus. Genes 7(10)Google Scholar
- Masai E, Yamada A, Healy JM, Hatta T, Kimbara K, Fukuda M, Yano K (1995) Characterization of biphenyl catabolic genes of gram-positive polychlorinated biphenyl degrader Rhodococcus sp. strain RHA1. Appl Environ Microbiol 61(6):2079–2085Google Scholar
- Miller JH (1972) Experiments in molecular genetics. Cold Spring Harbor Laboratory, Cold Spring HarborGoogle Scholar
- Sambrook J, Fritsch EF, Maniatis T (1989) Molecular cloning: a laboratory manual, 2nd edn. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NYGoogle Scholar
- Solovyev V, Salamov A (2011) Automatic annotation of microbial genomes and metagenomic sequences. Metagenomics and its application in agriculture, biomedicine and environmental studies:61–78Google Scholar