Screening sourdough samples for gliadin-degrading activity revealed Lactobacillus casei strains able to individually metabolize the coeliac-disease-related 33-mer peptide

Patricia Alvarez-Sieiro, Begoña Redruello, Victor Ladero, Maria Cruz Martín, María Fernández, Miguel A Alvarez

Research output: Contribution to journalArticleAcademicpeer-review

2 Citations (Scopus)

Abstract

A selective culture medium containing acid-hydrolyzed gliadins as the sole nitrogen source was used in the search for sourdough-indigenous lactic acid bacteria (LAB) with gliadin-metabolizing activity. Twenty gliadin-degrading LAB strains were isolated from 10 sourdoughs made in different ways and from different geographical regions. Fifteen of the 20 isolated strains were identified as Lactobacillus casei, a species usually reported as subdominant in sourdough populations. The other 5 gliadin-degrading strains belonged to the more commonly encountered sourdough species Leuconostoc mesenteroides and Lactobacillus plantarum. All these strains were shown to be safe in terms of their resistance to antimicrobial agents. When individually incubated with the α2-gliadin-derived immunotoxic 33-mer peptide (97.5 ppm), half of the L. casei strains metabolized at least 50% of it within 24 h. One strain metabolized 82% of the 33-mer peptide within 8 h and made it fully disappear within 12 h. These results reveal for the first time the presence in sourdough of proteolytic L. casei strains with the capacity to individually metabolize the coeliac-disease-related 33-mer peptide.

Original languageEnglish
Pages (from-to)422-430
Number of pages9
JournalCanadian Journal of Microbiology
Volume62
Issue number5
DOIs
Publication statusPublished - 2016
Externally publishedYes

Keywords

  • Bread/microbiology
  • Fermentation
  • Gliadin/metabolism
  • Hydrolysis
  • Lactobacillus casei/isolation & purification
  • Lactobacillus plantarum/metabolism
  • Peptide Fragments/metabolism
  • Peptides/metabolism

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