Wasteson Y, Høie S, Roberts M C
Department of Pathobiology, University of Washington, Seattle 98195.
Vet Microbiol. 1994 Jul;41(1-2):41-9. doi: 10.1016/0378-1135(94)90134-1.
Twenty one isolates of Streptococcus suis were screened for antibiotic resistance by growth on antibiotic-containing media, by measuring minimum inhibitory concentrations, by hybridization to specific DNA and oligonucleotide probes for antibiotic resistance genes, and by PCR. The isolates were from a slaughter house survey of respiratory pathogens in Norwegian pigs in 1986. Fifteen isolates were resistant to tetracycline, with MICs ranging from 4-128 micrograms/ml. Genes coding for the Tet O and Tet M determinants were detected in eight and five isolates, respectively. Genes coding for other Gram positive Tet determinants, Tet K, Tet L, and Tet P, were not detected. One isolate was constitutive resistant to erythromycin with MIC of 128 micrograms/ml. Five other isolates carried inducible erythromycin resistance. All these isolates, and five others, were positive in a PCR assay for erythromycin resistance, and hybridized with the Erm C and/or Erm B probes. No resistance against chloramphenicol (5 micrograms/ml) or rifampin (10 micrograms/ml) could be could be detected, but five isolates were resistant to streptomycin (250 micrograms/ml), four isolates were resistant to kanamycin (10 micrograms/ml), and one isolate was resistant to fusicic acid (10 micrograms/ml). In mating experiments with Enterococcus faecalis JH2-2 as recipient, tetracycline, erythromycin, and kanamycin genes were transferred separately to the recipient strain at a rate of 10(-7) transconjugants/recipient cell.
通过在含抗生素培养基上生长、测量最低抑菌浓度、与抗生素抗性基因的特异性DNA和寡核苷酸探针杂交以及PCR，对21株猪链球菌进行了抗生素抗性筛选。这些分离株来自1986年挪威猪呼吸道病原体的屠宰场调查。15株分离株对四环素耐药，最低抑菌浓度范围为4 - 128微克/毫升。分别在8株和5株分离株中检测到编码Tet O和Tet M决定簇的基因。未检测到编码其他革兰氏阳性Tet决定簇Tet K、Tet L和Tet P的基因。1株分离株对红霉素呈组成型耐药，最低抑菌浓度为128微克/毫升。另外5株分离株携带诱导型红霉素耐药性。所有这些分离株以及另外5株在红霉素抗性PCR检测中呈阳性，并与Erm C和/或Erm B探针杂交。未检测到对氯霉素（5微克/毫升）或利福平（10微克/毫升）的耐药性，但5株分离株对链霉素（250微克/毫升）耐药，4株分离株对卡那霉素（10微克/毫升）耐药，1株分离株对夫西地酸（10微克/毫升）耐药。在以粪肠球菌JH2 - 2作为受体的交配实验中，四环素、红霉素和卡那霉素基因分别以10(-7)转接合子/受体细胞的频率转移到受体菌株中。
