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Methods for Electroporation and Transformation Confirmation in Limosilactobacillus reuteri DSM20016
Published on: June 23, 2023
Evidence for plasmid-associated lactose metabolism inLactobacillus casei subsp.casei
B M Chassy1, E M Gibson, A Guiffrida
1Microbiology Section, Laboratory of Microbiology and Immunology, National Institute of Dental Research, National Institutes of Health, 20014, Bethesda, Maryland, USA.
Abstract:
Lac variants ofLactobacillus casei subsp.casei DR1002 (formerly 64H) have been produced using acriflavin, ethidium bromide, mitomycin C, or combinations of these agents. Two successive transfers in the presence of acriflavin and mitomycin C or ethidium bromide and mitomycin C resulted in nearly a 100% loss of lactose fermentation. Cesium chloride-ethidium bromide isopycnic gradient ultracentrifugal analysis of purified lysates demonstrated that the 23-mdal plasmid (pDR101) found inL. casei DR1002 was consistently absent in Lac(-) clones. We concluded that, as in lactic streptococci, lactose metablism is a plasmid-mediated train inL. casei DR1002.
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