Antibiotic-Efficient Genetic Cassette for the TEM-1 β-Lactamase That Improves Plasmid Performance.

Antibiotic resistance cassettes are indispensable tools in recombinant DNA technology, synthetic biology, and metabolic engineering. The genetic cassette encoding the TEM-1 β-lactamase (denoted Tn3.1) is one of the most commonly used and can be found in more than 120 commercially available bacterial expression plasmids (, the , , , , , , and series).