The integration and excision of CTnDOT

Bacteroides spp. are one of the more prevalent members of the human colonic microbiota, representing approximately 40% of the bacterial community (1). Bacteroides spp. are normally in symbiosis with their human hosts. Although they are usually harmless members of the gut microbiota, they can become opportunistic pathogens if released from the colon (2,3). This most commonly occurs due to surgery, trauma or disease such as gangrenous appendicitis or malignancies (4). Among anaerobic bacteria, Bacteroides spp. are the pathogens most commonly isolated from clinical samples, including blood (2). The treatment ofBacteroides infections has become more challenging as they have acquired a variety of genes that encode resistances to antibiotics. In the 1970s, only 20 to 30% of Bacteroides spp. clinical isolates were resistant to tetracycline. By the 1990s, the prevalence of tetracycline resistance had increased to 80% (5). This increase in tetracycline resistance can be attributed to the presence of integrative and conjugative elements (ICEs) that encode antibiotic resistance genes.