Mercury Resistance Determinants Related to Tn 21 , Tn 1696 , and Tn 5053 in Enterobacteria from the Preantibiotic Era

Abstract
Three mer transposons from the Murray collection of preantibiotic enterobacteria show >99% sequence identity to current isolates. Tn 5073 is most closely related to Tn 5036 and Tn 1696 , and Tn 5074 is most closely related to Tn 5053 . Tn 5075 is most closely related to Tn 21 but lacks integron In2 and is flanked by insertion elements.