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