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Updated: Aug 14, 2026

Site-Specific Lysine Lactylation via Genetic Code Expansion in E. coli and Mammalian Cells
Published on: February 24, 2026
Genetic Evidence for Plasmid-Linked Lactose Metabolism in Streptococcus lactis subsp. diacetylactis
1Department of Food Science and Nutrition, University of Minnesota, St. Paul, Minnesota 55108.
Abstract:
It has been previously observed that loss of plasmid pGK4101 occurred concomitantly with loss of lactose-fermenting ability in Streptococcus lactis subsp. diacetylactis 18-16. Transfer of this 41-megadalton plasmid to LM0230, a lactosenegative (Lac) strain of S. lactis, required cell-to-cell contact and resulted in a conversion of LM0230 to the Lac phenotype. This confirms the linkage of lactose-fermenting ability to the 41-megadalton plasmid in S. lactis subsp. diacetylactis and, in addition, demonstrates transfer by a process resembling conjugation in the group N streptococci.
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