Seol Sung Yong, Kim Yong Tae, Jeong Young Sook, Oh Jae Young, Kang Hee Young, Moon Dong Chan, Kim Jungmin, Lee Yoo Chul, Cho Dong Taek, Lee Je Chul
Department of Microbiology, Kyungpook National University School of Medicine, 101, Dongin-dong, Jung-gu, Daegu, 700-422, Korea.
J Med Microbiol. 2006 Jul;55(Pt 7):871-877. doi: 10.1099/jmm.0.46441-0.
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 blaTEM-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.
对1991年至2000年期间在韩国获得的122株宋内志贺菌分离株的抗菌耐药性进行了表征。这些分离株对传统抗生素如甲氧苄啶（100%）、链霉素（100%）、磺胺甲恶唑（94%）、四环素（93%）和萘啶酸（90%）具有高度耐药性。所有宋内志贺菌分离株在其染色体中携带Tn7。在93%的宋内志贺菌分离株中发现了携带tetA、strA-strB和sul1的8.4 kb非转移性耐药（R）质粒。对萘啶酸的耐药性于1997年首次出现在一株宋内志贺菌分离株中，然后在1998年和1999年的所有宋内志贺菌分离株中出现。在1998 - 2000年的暴发期间，宋内志贺菌分离株对常用抗生素如氨苄西林的耐药性有所增加。对氨苄西林的耐药性由携带blaTEM-1的接合性R质粒介导。总之，宋内志贺菌通过接合性R质粒的水平转移获得了对常用抗生素的抗菌耐药性，而转座子和非转移性R质粒的遗传稳定性导致了对传统抗生素的耐药性。
