Department of Biosciences, Nutrition and Food Biotechnology, University of Kuopio, Finland.
Benef Microbes. 2010 Mar;1(1):75-80. doi: 10.3920/BM2009.0002.
We aimed to determine the minimum inhibitory concentrations (MICs) of Lactobacillus rhamnosus (n=75) strains, to study their antibiotic resistance genes with microarray, and to assess the microbiological cut-off values of tested antimicrobial agents. L. rhamnosus strains were tested with agar dilution, broth microdilution and Etest methods for ampicillin, clindamycin, erythromycin, gentamicin, streptomycin, and tetracycline using specific LSM medium. Most of the L. rhamnosus strains were found phenotypically susceptible to all six antibiotics tested. Four of the strains were phenotypically multiresistant, three strains to clindamycin, erythromycin and streptomycin and one strain to streptomycin and tetracycline. Some of the resistant (n=8) and susceptible (n=5) strains were further studied with a microarray method to reveal the antibiotic resistance genes behind the phenotypic resistances. From our experience, we recommend that microbiological cut-off values should be proposed according to the method used.
我们旨在确定鼠李糖乳杆菌（n=75）菌株的最小抑菌浓度（MICs），用微阵列研究其抗生素耐药基因，并评估测试抗菌药物的微生物学临界值。使用特定的 LSM 培养基，通过琼脂稀释法、肉汤微量稀释法和 Etest 法对氨苄西林、克林霉素、红霉素、庆大霉素、链霉素和四环素对鼠李糖乳杆菌菌株进行了测试。大多数鼠李糖乳杆菌菌株对所有六种测试抗生素均表现出表型敏感性。有 4 株表现出表型多药耐药性，3 株对克林霉素、红霉素和链霉素耐药，1 株对链霉素和四环素耐药。一些耐药（n=8）和敏感（n=5）菌株进一步用微阵列方法进行了研究，以揭示表型耐药背后的抗生素耐药基因。根据我们的经验，我们建议根据所使用的方法提出微生物学临界值。
