GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.

Have any questions? Please email us at ecoliwiki@gmail.com

PMID:19589837

From GONUTS
Jump to: navigation, search
Citation

Yamamoto, M, Ueda, A, Kudo, M, Matsuo, Y, Fukushima, J, Nakae, T, Kaneko, T and Ishigatsubo, Y (2009) Role of MexZ and PA5471 in transcriptional regulation of mexXY in Pseudomonas aeruginosa. Microbiology (Reading, Engl.) 155:3312-21

Abstract

MexXY, a drug efflux pump in Pseudomonas aeruginosa, confers resistance to aminoglycoside antibiotics. We recently reported that MexZ binds to the promoter region of the mexXY operon. Electrophoretic mobility shift assay (EMSA) using recombinant MexZ and oligonucleotide probes prepared from the intergenic region between mexZ and mexX revealed that MexZ binds to a 20 bp palindromic sequence. Culture of P. aeruginosa in the presence of tetracycline induced higher levels of MexX and MexZ, as measured by immunoblotting and EMSA, than in the absence of antibiotics. When MexZ was expressed by a mexZ expression plasmid, the plasmid-borne MexZ repressed drug-induced MexX production, further confirming that MexZ acts as a repressor of the mexXY operon. PA5471 protein has been reported to be essential for drug-induced MexXY production. Similarly to that report, we observed that plasmid-borne PA5471 induced both MexX and MexZ production in PAO1 cells. Interestingly, interaction between MexZ and PA5471 was observed in a yeast two-hybrid assay. Furthermore, EMSA and in vitro transcription assays revealed that interaction between PA5471 and MexZ reduced MexZ DNA-binding ability, leading to mexXY transcription. These findings contribute to the understanding of the molecular mechanisms underlying the transcriptional regulation of mexZ and mexXY by drug-induced PA5471 expression.

Links

PubMed Online version:10.1099/mic.0.028993-0

Keywords

Anti-Bacterial Agents/pharmacology; Bacterial Proteins/biosynthesis; Bacterial Proteins/metabolism; Binding Sites; DNA, Bacterial/metabolism; Electrophoretic Mobility Shift Assay; Gene Expression Regulation, Bacterial; Promoter Regions, Genetic; Protein Binding; Pseudomonas aeruginosa/physiology; Repressor Proteins/metabolism; Tetracycline/pharmacology; Transcriptional Activation

Significance

Annotations

Gene product Qualifier GO Term Evidence Code with/from Aspect Extension Notes Status

PSEAE:G3XCU9

enables

GO:0000976: transcription regulatory region sequence-specific DNA binding

ECO:0005667: site-directed mutagenesis phenotypic evidence used in manual assertion

F

Seeded From UniProt

complete

PSEAE:G3XCU9

enables

GO:0001217: DNA-binding transcription repressor activity

ECO:0005667: site-directed mutagenesis phenotypic evidence used in manual assertion

F

Seeded From UniProt

complete

PSEAE:G3XCU9

part_of

GO:0032993: protein-DNA complex

ECO:0005667: site-directed mutagenesis phenotypic evidence used in manual assertion

C

Seeded From UniProt

complete

PSEAE:G3XCU9

involved_in

GO:0045892: negative regulation of transcription, DNA-templated

ECO:0000279: qualitative western immunoblotting evidence used in manual assertion

P

Seeded From UniProt

complete

PSEAE:G3XCU9

involved_in

GO:0045892: negative regulation of transcription, DNA-templated

ECO:0001204: in vitro transcription assay evidence used in manual assertion

P

Seeded From UniProt

complete

PSEAE:Q9ZH26

GO:0010629: negative regulation of gene expression

ECO:0000315:

P

Fig 3. Transformation with pEX-mexZ repressed mexX expression

complete


See also

References

See Help:References for how to manage references in GONUTS.