Ishiguro N, Goto J, Sato G
J Hyg (Lond). 1980 Jun;84(3):365-79. doi: 10.1017/s0022172400026899.
A total of 475 Salmonella strains belonging to 5 serovars, isolated from a pig farm which had been heavily contaminated with Salmonella for the past 2 years were tested for antibiotic susceptibility and detection of R plasmids. Thirty-three Escherichia coli isolates from the same farm were also examined in a similar way. Out of 475 strains 348 (73.2%) were resistant to one or more antibiotics such as tetracycline (Tc), streptomycin (Sm), sulfadimethoxine (Su), chloramphenicol (Cm) and kanamycin (Km), and 247 (85.2%) out of 290 strains belonging to 3 serovars examined harboured conjugative R plasmids. There was no change in the pattern of drug resistance during this survey nor any variation in the pattern of resistance of R plasmids, whatever the serovar. The antibiogram pattern Tc Sm Su, mainly S. typhimurium, was common among Salmonella strains. Among the transferred resistance patterns, the thermosensitive R plasmids conferring the Tc marker detected in this study were Fi-, and belonged to incompatibility group H1, whereas the R plasmids conferring Sm Su resistances which coexisted in the same host were Fi+, and compatible with the reference R plasmids tested. The I alpha plasmid conferring Cm resistance alone was isolated from S. anatum and the FII plasmid conferring Sm Km resistances was also isolated from S. typhimurium. In contrast, the 33 E. coli strains examined were resistant to three or five antibiotics and most of the resistance markers were located on conjugative R plasmids. I alpha plasmids conferring Cm resistance alone or FII plasmids conferring Cm or Km markers were common in the E. coli strains. H1 and H2 plasmids conferring multiple resistance markers were also found in them. The genetic properties of R plasmids derived from Salmonella or E. coli strains are compared, and the potential spread of R plasmids between strains of Salmonella and E. coli is discussed.
对从一个在过去两年中受到沙门氏菌严重污染的养猪场分离出的475株属于5个血清型的沙门氏菌菌株进行了抗生素敏感性测试和R质粒检测。还以类似方式检查了来自同一猪场的33株大肠杆菌分离株。在475株菌株中，348株（73.2%）对一种或多种抗生素耐药，如四环素（Tc）、链霉素（Sm）、磺胺二甲氧嘧啶（Su）、氯霉素（Cm）和卡那霉素（Km），在所检查的属于3个血清型的290株菌株中，有247株（85.2%）携带接合性R质粒。在本次调查期间，耐药模式没有变化，R质粒的耐药模式也没有任何变化，无论血清型如何。Tc Sm Su抗菌谱模式，主要是鼠伤寒沙门氏菌，在沙门氏菌菌株中很常见。在转移的耐药模式中，本研究中检测到的赋予Tc标记的热敏R质粒是Fi-，属于不相容群H1，而在同一宿主中共存的赋予Sm Su耐药性的R质粒是Fi+，与测试的参考R质粒相容。单独赋予Cm耐药性的Iα质粒从鸭沙门氏菌中分离出来，赋予Sm Km耐药性的FII质粒也从鼠伤寒沙门氏菌中分离出来。相比之下，所检查的33株大肠杆菌菌株对三种或五种抗生素耐药，大多数耐药标记位于接合性R质粒上。单独赋予Cm耐药性的Iα质粒或赋予Cm或Km标记的FII质粒在大肠杆菌菌株中很常见。还在其中发现了赋予多种耐药标记的H1和H2质粒。比较了源自沙门氏菌或大肠杆菌菌株的R质粒的遗传特性，并讨论了R质粒在沙门氏菌和大肠杆菌菌株之间潜在的传播情况。
