Mee B J, Nikoletti S M
J Appl Bacteriol. 1983 Apr;54(2):225-35. doi: 10.1111/j.1365-2672.1983.tb02611.x.
Trimethoprim (Tp) resistant Gram negative bacteria were isolated from humans and pigs. The bacterial hosts were characterized by their resistance pattern and biotype. The presence of transferable Tp plasmids was demonstrated in 86% of 59 porcine isolates and 37% of 49 human isolates. The Tp R-plasmids carried a diversity of resistance determinants such as Tc, Cm, Sp, Sm and Su. Incompatibility tests distinguished two major groups, Inc FIV and Inc N. Thirty of 99 Tp R-plasmids isolated from humans were grouped as Inc FIV and eight as Inc N. The results of molecular weight determination of Tp R-plasmids performed by agarose gel electrophoresis were consistent with the existence of two groups--larger R-plasmids (76 to 104 Md) belonging to Inc FIV and lower molecular weight R-plasmids (25 to 35 Md) belonging to Inc N. Results from this study indicate that the Tp R-plasmids isolated in Perth have evolved independently from those described in Europe and the United Kingdom. There is also evidence for their local spread between Escherichia, Klebsiella, Enterobacter, Citrobacter and Acinetobacter from man and animals.
从人和猪中分离出了对甲氧苄啶（Tp）耐药的革兰氏阴性菌。这些细菌宿主通过其耐药模式和生物型进行表征。在59株猪源分离株中的86%以及49株人源分离株中的37%中证实存在可转移的Tp质粒。Tp R质粒携带多种耐药决定因子，如对四环素（Tc）、氯霉素（Cm）、壮观霉素（Sp）、链霉素（Sm）和磺胺类药物（Su）的耐药决定因子。不相容性试验区分出两个主要组别，即Inc FIV和Inc N。从人分离出的99个Tp R质粒中，30个归为Inc FIV组，8个归为Inc N组。通过琼脂糖凝胶电泳对Tp R质粒进行分子量测定的结果与两组的存在情况相符——属于Inc FIV组的较大R质粒（76至104兆道尔顿）和属于Inc N组的较低分子量R质粒（25至35兆道尔顿）。本研究结果表明，在珀斯分离出的Tp R质粒是独立于欧洲和英国所描述的质粒进化而来的。也有证据表明它们在人和动物的大肠杆菌、克雷伯菌、肠杆菌、柠檬酸杆菌和不动杆菌之间在当地传播。
