Diverse Tetracycline Resistance Genotypes of Megasphaera elsdenii Strains Selectively Cultured from Swine Feces

Abstract
A total of 30 Megasphaera elsdenii strains, selectively isolated from the feces of organically raised swine by using Me109 M medium, and one bovine strain were analyzed for tetracycline resistance genotypic and phenotypic traits. Tetracycline-resistant strains carried tet (O), tet (W), or a tet gene mosaic of tet (O) and tet (W). M. elsdenii strains carrying tet (OWO) genes exhibited the highest tetracycline MICs (128 to >256 μg/ml), suggesting that tet (O)- tet (W) mosaic genes provide the selective advantage of greater tetracycline resistance for this species. Seven tet genotypes are now known for M. elsdenii , an archetype commensal anaerobe and model for tet gene evolution in the mammalian intestinal tract.

This publication has 25 references indexed in Scilit: