The Pseudomonas syringae pv. tomato DC3000 PSPTO_0820 multidrug transporter is involved in resistance to plant antimicrobials and bacterial survival during tomato plant infection

PLoS One. 2019 Jun 25;14(6):e0218815. doi: 10.1371/journal.pone.0218815. eCollection 2019.

Abstract

Multidrug resistance efflux pumps protect bacterial cells against a wide spectrum of antimicrobial compounds. PSPTO_0820 is a predicted multidrug transporter from the phytopathogenic bacterium Pseudomonas syringae pv. tomato DC3000. Orthologs of this protein are conserved within many Pseudomonas species that interact with plants. To study the potential role of PSPTO_0820 in plant-bacteria interaction, a mutant in this gene was isolated and characterized. In addition, with the aim to find the outer membrane channel for this efflux system, a mutant in PSPTO_4977, a TolC-like gene, was also analyzed. Both mutants were more susceptible to trans-cinnamic and chlorogenic acids and to the flavonoid (+)-catechin, when added to the culture medium. The expression level of both genes increased in the presence of (+)-catechin and, in the case of PSPTO_0820, also in response to trans-cinnamic acid. PSPTO_0820 and PSPTO_4977 mutants were unable to colonize tomato at high population levels. This work evidences the involvement of these two proteins in the resistance to plant antimicrobials, supporting also the importance of chlorogenic acid, trans-cinnamic acid, and (+)-catechin in the tomato plant defense response against P. syringae pv. tomato DC3000 infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B / metabolism*
  • Anti-Infective Agents / metabolism
  • Antimicrobial Cationic Peptides / metabolism
  • Bacterial Proteins / metabolism*
  • Genes, Bacterial
  • Host Microbial Interactions / genetics
  • Mutation
  • Plant Diseases / microbiology*
  • Plant Proteins / metabolism
  • Pseudomonas syringae / metabolism*
  • Pseudomonas syringae / pathogenicity*
  • Solanum lycopersicum / metabolism
  • Solanum lycopersicum / microbiology*
  • Virulence / genetics

Substances

  • ATP Binding Cassette Transporter, Subfamily B
  • Anti-Infective Agents
  • Antimicrobial Cationic Peptides
  • Bacterial Proteins
  • Plant Proteins

Grants and funding

This research has been supported by the Spanish Plan Nacional I+D+i grants AGL-2012-32516 and AGL 2015-63851-R. JJRH was funded by the Ramón y Cajal program from the Spanish Ministry of Science and Innovation (RYC-2007-01045). PMMG was supported by the Campus de Excelencia Internacional Andalucía TECH. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.