Genetic diversity in the lactose operons of Lactobacillus helveticus strains and its relationship to the role of these strains as commercial starter cultures.

نویسندگان

  • M J Callanan
  • T P Beresford
  • R P Ross
چکیده

Two novel insertion sequence elements, ISLhe1 and ISLhe15, were located upstream of the genes encoding the beta-galactosidase enzyme in Lactobacillus helveticus commercial starter strains. Strains with the IS982 family element, ISLhe1, demonstrated reduced beta-galactosidase activity compared to the L. helveticus type strain, whereas strains with the ISLhe15 element expressed beta-galactosidase in the absence of lactose.

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عنوان ژورنال:
  • Applied and environmental microbiology

دوره 71 3  شماره 

صفحات  -

تاریخ انتشار 2005