Endophytic bacterial communities in peels and pulp of five root vegetables

PLoS One. 2019 Jan 11;14(1):e0210542. doi: 10.1371/journal.pone.0210542. eCollection 2019.

Abstract

Plants contain endophytic bacteria, whose communities both influence plant growth and can be an important source of probiotics. Here we used deep sequencing of a 16S rRNA gene fragment and bacterial cultivation to independently characterize the microbiomes of five plant species from divergent taxonomic orders-potato (Solanum tuberosum), carrot (Daucus sativus), beet (Beta vulgaris), neep (Brassica napus spp. napobrassica), and topinambur (Helianthus tuberosus). We found that both species richness and diversity tend to be higher in the peel, where Alphaproteobacteria and Actinobacteria dominate, while Gammaproteobacteria and Firmicutes dominate in the pulp. A statistical analysis revealed that the main characteristic features of the microbiomes of plant species originate from the peel microbiomes. Topinambur pulp displayed an interesting characteristic feature: it contained up to 108 CFUs of lactic acid bacteria, suggesting its use as a source of probiotic bacteria. We also detected Listeria sp., in topinambur pulps, however, the 16S rRNA gene fragment is unable to distinguish between pathogenic versus non-pathogenic species, so the evaluation of this potential health risk is left to a future study.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteria / classification
  • Bacteria / genetics*
  • Bacteria / growth & development
  • Beta vulgaris / microbiology
  • Beta vulgaris / physiology
  • Brassica napus / microbiology
  • Brassica napus / physiology
  • DNA, Bacterial / genetics
  • Daucus carota / microbiology
  • Daucus carota / physiology
  • Ecosystem*
  • Endophytes / classification
  • Endophytes / genetics*
  • Endophytes / physiology
  • Helianthus / microbiology
  • Helianthus / physiology
  • Microbiota / genetics
  • Phylogeny
  • RNA, Ribosomal, 16S / genetics
  • Sequence Analysis, DNA / methods
  • Solanum tuberosum / microbiology
  • Solanum tuberosum / physiology
  • Vegetables / classification
  • Vegetables / microbiology
  • Vegetables / physiology*

Substances

  • DNA, Bacterial
  • RNA, Ribosomal, 16S

Grants and funding

TT, ÜM, VK, KA: Estonian Research Council IUT2-22. https://www.etis.ee/Portal/Projects/Display/db4a3ea8-611d-4be5-af16-a18d2d861873?lang=ENG. MR, MRo: Estonian Research Council IUT34-11. https://www.etis.ee/Portal/Projects/Display/2493d2a9-1edf-4a53-a6d1-9cbf469758c3?lang=ENG. TT, ÜM: European Union from the European Regional Development Fund through the Centre of Excellence in Molecular Cell Engineering SLTTI16143T https://www.etis.ee/Portal/Projects/Display/e6209fe6-9b6a-4a8e-9ad4-89ecc5c60cc2?lang=ENG. Ki: Estonian Research Council PUT-134 https://www.etis.ee/Portal/Projects/Display/08c424fe-696c-45cb-9bc0-fdd02f9af2a2?lang=ENG. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.