Presence of galactose in precultures induces lacS and leads to short lag phase in lactose-grown Lactococcus lactis cultures
Journal article, 2018

Lactose conversion by lactic acid bacteria is of high industrial relevance and consistent starter culture quality is of outmost importance. We observed that Lactococcus lactis using the high-affinity lactose-phosphotransferase system excreted galactose towards the end of the lactose consumption phase. The excreted galactose was re-consumed after lactose depletion. The lacSgene, known to encode a lactose permease with affinity for galactose, a putative galactose–lactose antiporter, was upregulated under the conditions studied. When transferring cells from anaerobic to respiration-permissive conditions, lactose-assimilating strains exhibited a long and non-reproducible lag phase. Through systematic preculture experiments, the presence of galactose in the precultures was correlated to short and reproducible lag phases in respiration-permissive main cultivations. For starter culture production, the presence of galactose during propagation of dairy strains can provide a physiological marker for short culture lag phase in lactose-grown cultures.

Galactose–lactose antiporter

Galactose

Lag phase

Starter cultures

Lactococcus lactis

Author

Bettina Lorantfy

Chalmers, Biology and Biological Engineering, Industrial Biotechnology

Anna Johanson

Chalmers, Biology and Biological Engineering, Industrial Biotechnology

Fábio Luis Da Silva Faria Oliveira

Chalmers, Biology and Biological Engineering, Industrial Biotechnology

Carl Johan Franzén

Chalmers, Biology and Biological Engineering, Industrial Biotechnology

Valeria Mapelli

Chalmers, Biology and Biological Engineering, Industrial Biotechnology

Lisbeth Olsson

Chalmers, Biology and Biological Engineering, Industrial Biotechnology

Journal of Industrial Microbiology and Biotechnology

1367-5435 (ISSN) 1476-5535 (eISSN)

1-11

Subject Categories

Food Engineering

Microbiology

Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)

Roots

Basic sciences

Areas of Advance

Life Science Engineering (2010-2018)

DOI

10.1007/s10295-018-2099-0

More information

Created

11/22/2018