Tetracycline Resistance Mediated by <i>tet</i> (W), <i>tet</i> (M), and <i>tet</i> (O) Genes of <i>Bifidobacterium</i> Isolates from Humans

Abstract

MICs of tetracyclines were determined for 86 human Bifidobacterium isolates and three environmental strains. The tet(O) gene was found to be absent in these isolates. tet(W) and tet(M) were found in 26 and 7%, respectively, of the Bifidobacterium isolates, and one isolate contained both genes. Chromosomal DNA hybridization showed that there was one chromosomal copy of tet(W) and/or tet(M).