The Lrp/AsnC-Type Regulator PA2577 Controls the EamA-like Transporter Gene <i>PA2576</i> in <i>Pseudomonas aeruginosa</i>
The regulatory network of gene expression in <i>Pseudomonas aeruginosa</i>, an opportunistic human pathogen, is very complex. In the PAO1 reference strain, about 10% of genes encode transcriptional regulators, many of which have undefined regulons and unknown functions. The aim of this s...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-12-01
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| Series: | International Journal of Molecular Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1422-0067/22/24/13340 |
| Summary: | The regulatory network of gene expression in <i>Pseudomonas aeruginosa</i>, an opportunistic human pathogen, is very complex. In the PAO1 reference strain, about 10% of genes encode transcriptional regulators, many of which have undefined regulons and unknown functions. The aim of this study is the characterization of PA2577 protein, a representative of the Lrp/AsnC family of transcriptional regulators. This family encompasses proteins involved in the amino acid metabolism, regulation of transport processes or cell morphogenesis. The transcriptome profiling of <i>P. aeruginosa</i> cells with mild PA2577 overproduction revealed a decreased expression of the <i>PA2576</i> gene oriented divergently to <i>PA2577</i> and encoding an EamA-like transporter. A gene expression analysis showed a higher mRNA level of <i>PA2576</i> in <i>P. aeruginosa</i> Δ<i>PA2577</i>, indicating that PA2577 acts as a repressor. Concomitantly, ChIP-seq and EMSA assays confirmed strong interactions of PA2577 with the <i>PA2577</i>/<i>PA2576</i> intergenic region. Additionally, phenotype microarray analyses indicated an impaired metabolism of Δ<i>PA2576</i> and Δ<i>PA2577</i> mutants in the presence of polymyxin B, which suggests disturbances of membrane functions in these mutants. We show that PA2576 interacts with two proteins, PA5006 and PA3694, with a predicted role in lipopolysaccharide (LPS) and membrane biogenesis. Overall, our results indicate that PA2577 acts as a repressor of the <i>PA2576</i> gene coding for the EamA-like transporter and may play a role in the modulation of the cellular response to stress conditions, including antimicrobial peptides, e.g., polymyxin B. |
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| ISSN: | 1661-6596 1422-0067 |