RRC ID 80720
Author Nemoto N, Kurihara S, Kitahara Y, Asada K, Kato K, Suzuki H.
Title Mechanism for regulation of the putrescine utilization pathway by the transcription factor PuuR in Escherichia coli K-12.
Journal J Bacteriol
Abstract In Escherichia coli, putrescine is metabolized to succinate for use as a carbon and nitrogen source by the putrescine utilization pathway (Puu pathway). One gene in the puu gene cluster encodes a transcription factor, PuuR, which has a helix-turn-helix DNA-binding motif. DNA microarray analysis of an E. coli puuR mutant, in which three amino acid residues in the helix-turn-helix DNA binding motif of PuuR were mutated to alanine to eliminate DNA binding of PuuR, suggested that PuuR is a negative regulator of puu genes. Results of gel shift and DNase I footprint analyses suggested that PuuR binds to the promoter regions of puuA and puuD. The binding of wild-type PuuR to a DNA probe containing PuuR recognition sites was diminished with increasing putrescine concentrations in vitro. These results suggest that PuuR regulates the intracellular putrescine concentration by the transcriptional regulation of genes in the Puu pathway, including puuR itself. The puu gene cluster is found in E. coli and closely related enterobacteria, but this gene cluster is uncommon in other bacterial groups. E. coli and related enterobacteria may have gained the Puu pathway as an adaptation for survival in the mammalian intestine, an environment in which polyamines exist at relatively high concentrations.
Volume 194(13)
Pages 3437-47
Published 2012-7-1
DOI 10.1128/JB.00097-12
PII JB.00097-12
PMID 22522900
PMC PMC3434745
MeSH Binding Sites DNA Footprinting DNA, Bacterial / genetics DNA, Bacterial / metabolism DNA-Binding Proteins / chemistry DNA-Binding Proteins / genetics DNA-Binding Proteins / metabolism Electrophoretic Mobility Shift Assay Escherichia coli K12 / genetics Escherichia coli K12 / metabolism* Escherichia coli Proteins / genetics Escherichia coli Proteins / metabolism* Gene Expression Regulation, Bacterial* Helix-Turn-Helix Motifs / genetics Multigene Family Mutation Oligonucleotide Array Sequence Analysis Putrescine / chemistry Putrescine / metabolism* Transcription Factors / genetics Transcription Factors / metabolism*
IF 3.006
Resource
Prokaryotes E. coli ME10026