“…Class 1 integron has been commonly reported in a large variety of clinical gram-negative organisms, including Acinetobacter, Aeromonas, Alcaligenes, Burkholderia, Campylobacter, Citrobacter, Enterobacter, Escherichia, Klebsiella, Mycobacterium, Pseudomonas, Salmonella, Serratia, Shigella and Vibrio, and occasionally observed Yu et al 1303 in Campylobacter jejuni, Providencia stuartii, Serratia marcescens, Stenotrophomonas maltophilia, with a broad distribution of 22-59% (Clark et al, 1999;Nandi et al, 2004;Nesvera J, 1998;Tauch et al, 2002;Arakawa et al, 1995;Lee et al, 2002;Chang et al, 2004;Li et al, 2002;Isabelle Plante, 2003;Ruiz et al, 2004). Regarded as a primary source of antimicrobial resistance genes and reservoirs and exchanging platforms of resistance genes within microbial populations, the role of class 1 integron in the dissemination of antibiotic resistance genes had been well investigated and documented in a large number of gram-negative bacteria (Labbate et al, 2009;Maguire et al, 2001;Martinez-Freijo et al, 1998;Sallen et al, 1995).…”