Evaluation of repetitive-PCR and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for rapid strain typing of Bacillus coagulans

PLoS One. 2017 Oct 11;12(10):e0186327. doi: 10.1371/journal.pone.0186327. eCollection 2017.

Abstract

In order to establish rapid and accurate typing method for Bacillus coagulans strains which is important for controlling in some canned foods and tea-based beverages manufacturing because of the high-heat resistance of the spores and high tolerance of the vegetative cells to catechins and chemicals, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and repetitive-PCR (rep-PCR) were evaluated. For this purpose, 28 strains of B. coagulans obtained from various culture collections were tested. DNA sequence analyses of the genes encoding 16S rRNA and DNA gyrase classified the test strains into two and three groups, respectively, regardless of their phenotypes. Both MALDI-TOF MS and rep-PCR methods classified the test strains in great detail. Strains classified in each group showed similar phenotypes, such as carbohydrate utilization determined using API 50CH. In particular, the respective two pairs of strains which showed the same metabolic characteristic were classified into the same group by both MALDI-TOF MS and rep-PCR methods separating from the other strains. On the other hand, the other strains which have the different profiles of carbohydrate utilization were separated into different groups by these methods. These results suggested that the combination of MALDI-TOF MS and rep-PCR analyses was advantageous for the rapid and detailed typing of bacterial strains in respect to both phenotype and genotype.

MeSH terms

  • Bacillus coagulans / genetics*
  • Bacillus coagulans / metabolism
  • Base Sequence
  • Carbohydrate Metabolism
  • Cluster Analysis
  • DNA Gyrase / metabolism
  • DNA, Ribosomal Spacer / genetics
  • Molecular Typing / methods*
  • Phylogeny
  • Polymerase Chain Reaction / methods*
  • Polymorphism, Single Nucleotide / genetics
  • RNA, Ribosomal, 16S / genetics
  • Ribotyping
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / methods*

Substances

  • DNA, Ribosomal Spacer
  • RNA, Ribosomal, 16S
  • DNA Gyrase

Grants and funding

The funder, Kao Corporation, provided support in the form of salaries for authors JS, MN, AT, TS, and MH. The funder made a contract of collaborative study with TM, Kyushu University. TM had a role in review and editing of the manuscript. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.