Mutations in Neisseria gonorrhoeae grown in sub-lethal concentrations of monocaprin do not confer resistance

PLoS One. 2018 Apr 5;13(4):e0195453. doi: 10.1371/journal.pone.0195453. eCollection 2018.

Abstract

Neisseria gonorrhoeae, due to its short lipooligosaccharide structure, is generally more sensitive to the antimicrobial effects of some fatty acids than most other Gram negative bacteria. This supports recent development of a fatty acid-based potential treatment for gonococcal infections, particularly ophthalmia neonatorum. The N. gonorrhoeae genome contains genes for fatty acid resistance. In this study, the potential for genomic mutations that could lead to resistance to this potential new treatment were investigated. N. gonorrhoeae strain NCCP11945 was repeatedly passaged on growth media containing a sub-lethal concentration of fatty acid myristic acid and monoglyceride monocaprin. Cultures were re-sequenced and assessed for changes in minimum inhibitory concentration. Of note, monocaprin grown cultures developed a mutation in transcription factor gene dksA, which suppresses molecular chaperone DnaK and may be involved in the stress response. The minimum inhibitory concentration after exposure to monocaprin showed a modest two-fold change. The results of this study suggest that N. gonorrhoeae cannot readily evolve resistance that will impact treatment of ophthalmia neonatorum with monocaprin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Bacterial Proteins / genetics
  • Drug Resistance, Bacterial / genetics*
  • Glycerides / pharmacology*
  • Humans
  • Microbial Sensitivity Tests
  • Molecular Chaperones / antagonists & inhibitors
  • Myristic Acid / pharmacology*
  • Neisseria gonorrhoeae / drug effects*
  • Neisseria gonorrhoeae / genetics*
  • Ophthalmia Neonatorum / drug therapy*
  • Ophthalmia Neonatorum / microbiology
  • Polymorphism, Single Nucleotide / genetics
  • Transcription Factors / genetics

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Glycerides
  • Molecular Chaperones
  • Transcription Factors
  • Myristic Acid
  • rac-glycerol 1-monodecanoate

Grants and funding

This work was supported by the Sparks Children’s Medical Research charity (www.sparks.org.uk), which has provided for this work with Project Grants 11KIN01 and 13KIN01 to support Colin Churchward and this research. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.