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Updated: Aug 15, 2026

Generation of a Gene-disrupted Streptococcus mutans Strain Without Gene Cloning
Published on: October 23, 2017
Passive immunization by lactobacilli expressing single-chain antibodies against Streptococcus mutans
Carina Krüger1, Anna Hultberg, Craig van Dollenweerd
1Division of Clinical Immunology, Karolinska Institutet at Karolinska Huddinge, SE-141 86, Huddinge, Sweden.
Abstract:
We compared the anticariogenic effect of lactobacilli expressing a single-chain antibody (scFv) against the SA I/II adhesin of Streptococcus mutans under the control of an inducible or a constitutive promoter. Both lactobacilli expressed equal amounts of scFv and agglutinated S. mutans bacteria expressing SA I/II to a similar level. In a rat caries model, transformed lactobacilli could be detected in the oral cavity throughout the duration of the study. Transformants containing the constitutive promoter were slightly more protective than those containing the inducible promoter suggesting that continuous in situ production of scFv in the oral cavity may be therapeutically superior to intermittent production.
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