...PMCID: PMC3748948.
Khetrapal, Varnica, et al. "A set of powerful negative selection systems for unmodified...expression of a gene with an antibiotic resistance cassette. This leaves a “scar” in the chromosome, sometimes...vector contains sacB, an chloramphenicol resistance cassette, and the R6K origin of replication to allow replication...pDS132 (Philippe et al., 2004):
Replaced the sacB cassette with one of three toxins from the Khetrapal paper...medicine and clinical infectious diseases at the Massachusetts General Hospital where he is now an attending...