The EbpA-RpoN regulatory pathway of the pathogen Leptospira interrogans is essential for survival in the environment

Wei Lin Hu, Christopher J. Pappas, Jun Jie Zhang, You Yun Yang, Jie Yan, Mathieu Picardeau, X. Yang

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Leptospira interrogans is the agent of leptospirosis, a reemerging zoonotic disease. It is transmitted to humans through environmental surface waters contaminated by the urine of mammals chronically infected by pathogenic strains able to survive in water for long periods. Little is known about the regulatory pathways underlying environmental sensing and host adaptation of L. interrogans during its enzootic cycle. This study identifies the EbpA-RpoN regulatory pathway in L. interrogans. In this pathway, EbpA, a σ54 activator and putative prokaryotic enhancerbinding protein (EBP), and the alternative sigma factor RpoN (σ54) control expression of at least three genes, encoding AmtB (an ammonium transport protein) and two proteins of unknown function. Electrophoresis mobility shift assay demonstrated that recombinant RpoN and EbpA bind to the promoter region and upstream of these three identified genes, respectively. Genetic disruption of ebpA in L. interrogans serovar Manilae virtually abolished expression of the three genes, including amtB in two independent ebpA mutants. Complementation of the ebpA mutant restored expression of these genes. Intraperitoneal inoculation of gerbils with the ebpA mutant did not affect mortality. However, the ebpA mutant had decreased cell length in vitro and had a significantly lowered cell density at stationary phase when grown with L-alanine as the sole nitrogen source. Furthermore, the ebpA mutant has dramatically reduced long-term survival ability in water. Together, these studies identify a regulatory pathway, the EbpA-RpoN pathway, that plays an important role in the zoonotic cycle of L. interrogans.

Original languageEnglish (US)
Article numbere02377-16
JournalApplied and Environmental Microbiology
Volume83
Issue number3
DOIs
StatePublished - 2017

Fingerprint

Leptospira interrogans
pathogen
mutants
Survival
pathogens
gene
Zoonoses
RNA Polymerase Sigma 54
protein
Water
sigma factors
Gene Expression
Leptospirosis
gerbils
genes
Gerbillinae
leptospirosis
transport proteins
Electrophoretic Mobility Shift Assay
zoonoses

Keywords

  • Leptospira
  • Leptospirosis
  • RpoN
  • Spirochete

ASJC Scopus subject areas

  • Biotechnology
  • Food Science
  • Applied Microbiology and Biotechnology
  • Ecology

Cite this

The EbpA-RpoN regulatory pathway of the pathogen Leptospira interrogans is essential for survival in the environment. / Hu, Wei Lin; Pappas, Christopher J.; Zhang, Jun Jie; Yang, You Yun; Yan, Jie; Picardeau, Mathieu; Yang, X.

In: Applied and Environmental Microbiology, Vol. 83, No. 3, e02377-16, 2017.

Research output: Contribution to journalArticle

Hu, Wei Lin ; Pappas, Christopher J. ; Zhang, Jun Jie ; Yang, You Yun ; Yan, Jie ; Picardeau, Mathieu ; Yang, X. / The EbpA-RpoN regulatory pathway of the pathogen Leptospira interrogans is essential for survival in the environment. In: Applied and Environmental Microbiology. 2017 ; Vol. 83, No. 3.
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AU - Picardeau, Mathieu

AU - Yang, X.

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