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

ABSTRACT: 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.

SUBMITTER: Callanan MJ

PROVIDER: S-EPMC1065143 | biostudies-literature | 2005 Mar

REPOSITORIES: biostudies-literature

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

Callanan M J MJ Beresford T P TP Ross R P RP

Applied and environmental microbiology 20050301 3

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. ...[more]

PMID: 15746373

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