Characterization of the GntR family regulator HpaR1 of the crucifer black rot pathogen Xanthomonas campestris pathovar campestris.
Sci Rep
; 6: 19862, 2016 Jan 28.
Article
em En
| MEDLINE
| ID: mdl-26818230
ABSTRACT
The GntR family transcription regulator HpaR1 identified from Xanthomonas campestris pv. campestris has been previously shown to positively regulate the genes responsible for hypersensitive reaction and pathogenicity and to autorepress its own expression. Here, we demonstrated that HpaR1 is a global regulator that positively regulates diverse biological processes, including xanthan polysaccharide production, extracellular enzyme activity, cell motility and tolerance to various stresses. To investigate the regulatory mechanisms of HpaR1, we began with xanthan polysaccharide production, which is governed by a cluster of gum genes. These are directed by the gumB promoter. Disruption of HpaR1 significantly reduced gumB transcription and an electrophoretic mobility shift assay demonstrated that HpaR1 interacts directly with gumB promoter. DNase I footprint analysis revealed that HpaR1 and RNA polymerase were bound to the sequences extending from -21 to +10 and -41 to +29 relative to the transcription initiation site of gumB, respectively. Furthermore, in vitro transcription assays showed that HpaR1 facilitated the binding of RNA polymerase to gumB promoter, leading to an enhancement of its transcription. These results suggest that HpaR1 regulates gumB transcription via a mechanism similar but different to what was found, until now, to only be used by some MerR family transcription activators.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
/
Fatores de Transcrição
/
Xanthomonas campestris
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Sci Rep
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
China