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Last update: May 2021

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Internet de l'unité STLO Science et Technologie du Lait et de l'Oeuf

STLO Research Unit

Propionibacterium freudenreichii is what it eats

Api gallery
Propionibacterium freudenreichii (PF) is a dairy bacterial species widely used in cheese manufacturing and is also recognized for its probiotic and biotechnological properties. Lactate is the most common carbon source used to grow PF in the industry. For economical or sustainable reasons, it would be interesting to diversify the source of carbon (sugar). We investigated which sugar PF is able to utilise and whether we can predict its capabilities by reading its DNA.


The study of the growth of 21 PF strains on 50 different sugars revealed that:

  • 8 sugars are degraded by all strains. These traits help characterise the species.
  • 9 sugars are or are not degraded according to the strain.
  • 33 sugars were not degraded by any of the strains.

We sequenced the whole genome of the 21 strains and compared each of them to find the genes responsible for these sugar degradation capabilities:

  • The degradation of lactose and melibiose is governed by 2 genomic islands which encode the transport and degradation of these sugars
  • Genes responsible for the degradation of gluconate and ribose were deciphered. The presence of nonsense mutations prevents certain strains from degrading these sugars.


Visuel 350x372 B2ISI MR20

Choice of the right strain according to the sugar to be fermented. For example, strains capable of degrading gluconate are useful for probiotic application since gluconate is present in the intestinal tract. Strains capable of degrading ribose are considered for white biotechnology applications.


Knowledge on the genetic basis of sugar degradation opens new strategies for the high throughput screening of P. freudenreichii strains collection using biomolecular tools to optimize cheese starters, as well as probiotics and prebiotics and white biotechnology applications.





MaIAGE INRA, Domaine de Vilvert, JOUY-EN-JOSAS

This work was supported by a research grant AIP Bioressources 2009 founded by INRA

Read more

V. Loux, M Mariadassou, S Almeida, H Chiapello, A Hammani, J Buratti, A Gendrault, V Barbe, J-M Aury, S-M Deutsch, S Parayre, M-N Madec, V Chuat, G Jan, P Peterlongo, V Azevedo, Y Le Loir and H Falentin (2015) Mutations and genomic islands can explain the strain dependency of sugar utilization in 21 strains of Propionibacterium freudenreichii.BMC Genomics 16:296 doi 10.1186/s12864-015-1467-7


Hélène Falentin •

>>> To Research Team