Résumé
INTRODUCTION: The yeast Candida anglica had only been isolated from cider. As part of the MetaPDOcheese project, which aimed to explore the diversity of microbial communities inhabiting 44 of the 46 PDO (Protected Designation of Origin) cheeses, 29 isolates of C. anglica were found in three PDO cheeses from 6 dairies. Metabarcoding analysis of the cheese microbiota showed that the read abundance of C. anglica reached more than 28% in some cheese samples, suggesting that this species may play a role in cheese ripening, although it has never been identified in cheese.OBJECTIVE: The aim of this study was to characterise the genetic and phenotypic diversity of the C. anglica strains, to search for putative signatures of adaptation to cheese and cider, and to hypothesise about their role in fermented foods.MATERIALS AND METHODS: The genomes of eight strains were sequenced and analysed using a population genomics approach. Phenotypic traits were studied by quantitative measurements of growth under different conditions.RESULTS AND DISCUSSION: The genomes of three cheese strains and of the cider strain were assembled and annotated, resulting in assemblies of 13.7 Mb and a core genome of 5,966 coding sequences. Phylogenetic analysis showed that the seven cheese strains clustered together, away from the cider strain. Extremely low nucleotide diversity was observed within the cheese strains, suggesting that they could be maintained in the dairies throughout the year and exchanged between producers via equipment, starters, or ripening cultures. Phenotypic trait variations were observed within the cheese population under stress conditions, while the cider strain was found to have a much greater capacity for growth under all conditions tested.CONCLUSION/PERSPECTIVES: The study of the genotype-phenotype relationships showed a potential adaptation of C. anglica strains to the cheese and cider environments, but their role still remains to be elucidated.