RT Journal Article SR Electronic(1) A1 Seol, Sung Yong A1 Kim, Yong Tae A1 Jeong, Young Sook A1 Oh, Jae Young A1 Kang, Hee Young A1 Moon, Dong Chan A1 Kim, Jungmin A1 Lee, Yoo Chul A1 Cho, Dong Taek A1 Lee, Je ChulYR 2006 T1 Molecular characterization of antimicrobial resistance in Shigella sonnei isolates in Korea JF Journal of Medical Microbiology, VO 55 IS 7 SP 871 OP 877 DO https://doi.org/10.1099/jmm.0.46441-0 PB Microbiology Society, SN 1473-5644, AB The antimicrobial resistance of 122 Shigella sonnei isolates obtained in Korea during the period 1991–2000 was characterized. These isolates were highly resistant to traditional antibiotics such as trimethoprim (100 %), streptomycin (100 %), sulfamethoxazole (94 %), tetracycline (93 %) and nalidixic acid (90 %). All S. sonnei isolates carried Tn7 in their chromosomes. The 8.4 kb non-transferable resistance (R) plasmid carrying tetA, strA-strB and sul1 was found in 93 % of the S. sonnei isolates. Resistance to nalidixic acid first appeared in a S. sonnei isolate in 1997, and then in all S. sonnei isolates from 1998 and 1999. Resistance to commonly prescribed antibiotics such as ampicillin was increased in S. sonnei isolates during the outbreak period 1998–2000. Resistance to ampicillin was mediated by the conjugative R plasmids carrying bla TEM-1. In conclusion, S. sonnei acquired antimicrobial resistance to commonly prescribed antibiotics through the horizontal transfer of conjugative R plasmids, while the genetic stability of transposon and non-transferable R plasmids was responsible for resistance to traditional antibiotics., UL https://www.microbiologyresearch.org/content/journal/jmm/10.1099/jmm.0.46441-0