Monego Fernanda, Maboni Franciele, Krewer Cristina, Vargas Agueda, Costa Mateus, Loreto Elgion
Medicina Veteirnaria Preventiva, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil.
Curr Microbiol. 2009 Apr;58(4):399-403. doi: 10.1007/s00284-009-9370-6. Epub 2009 Feb 10.
This study evaluated the molecular characteristics of Rhodococcus equi isolates obtained from horses by a multiplex PCR assay that amplifies the vap gene family (vapA, -B, -C, -D, -E, -F, -G, and -H). A total of 180 R. equi isolates were studied from four different sources, namely healthy horse feces (112), soil (12), stalls (23), and clinical isolates (33) from horse-breeding farms. The technique was performed and confirmed by sequencing of amplified vap gene family controls. Thirty-two (17.8%) of the R. equi isolates were positive for the vapA gene and carried at least three other vap genes. All 147 isolates from equine feces, stalls, and soil failed to demonstrate any genes associated with virulence-inducing proteins. About 32 (97.0%) out of the 33 clinical equine isolates tested positive for the multiplex PCR assay for the vap gene family. They demonstrated six molecular profiles: 100% featured the vapA, vapD, and vapG genes, 86.6% vapF, 76.6% vapH, 43.3% vapC, 36.6% vapE, and none vapB. The most frequent molecular profile was vap A, -D, -F, G, and -H, where this profile was present in 37.5% of the strains. Moreover, there was no molecular epidemiological pattern for R. equi isolates that uniquely mapped to each horse-breeding farm studied. Our proposed technique allows the identification of eight members of the vap gene family (vapA, B, -C, -D, -E, -F, -G, and -H). It is a practical and efficient method of conducting clinical and epidemiological studies on R. equi isolates.
本研究通过多重聚合酶链反应（PCR）分析评估了从马匹中分离出的马红球菌菌株的分子特征，该分析可扩增vap基因家族（vapA、-B、-C、-D、-E、-F、-G和-H）。共研究了来自四个不同来源的180株马红球菌菌株，即健康马粪便（112株）、土壤（12株）、畜栏（23株）以及来自养马场的临床分离株（33株）。通过对扩增的vap基因家族对照进行测序，对该技术进行了操作和验证。32株（17.8%）马红球菌菌株的vapA基因呈阳性，并携带至少其他三个vap基因。来自马粪便、畜栏和土壤的所有147株分离株均未显示出任何与毒力诱导蛋白相关的基因。在33株临床马分离株中，约32株（97.0%）的vap基因家族多重PCR检测呈阳性。它们表现出六种分子谱：100%具有vapA、vapD和vapG基因，86.6%具有vapF，76.6%具有vapH，43.3%具有vapC，36.6%具有vapE，无vapB。最常见的分子谱是vap A、-D、-F、G和-H，该谱在37.5%的菌株中存在。此外，对于所研究的每个养马场，马红球菌分离株没有独特的分子流行病学模式。我们提出的技术可鉴定vap基因家族的八个成员（vapA、B、-C、-D、-E、-F、-G和-H）。这是一种对马红球菌分离株进行临床和流行病学研究的实用且有效的方法。
