title: The transposons Tn501(Hg) and Tn1721(Tc) are related.
mesh_terms: D005075:Biological Evolution; D004251:DNA Transposable Elements; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000235:genetics; D008628:Mercury; D013752:Tetracycline
chemical_list: D004251:DNA Transposable Elements; D013752:Tetracycline; D008628:Mercury