Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, Hungária körút 21, Budapest 1143, Hungary.
Instituto Zooprofilattico Sperimentale delle Venezie, Via San Giacomo 5, Verona 37000, Italy.
Vet Microbiol. 2019 Apr;231:191-196. doi: 10.1016/j.vetmic.2019.03.016. Epub 2019 Mar 15.
Mycoplasma gallisepticum causes chronic respiratory disease and reproductive disorders in many bird species, resulting in considerable economic losses to the poultry industry. Maintenance of M. gallisepticum-free flocks is the most adequate method to control infection. To this end, monitoring systems and vaccination programs with live vaccine strains are applied worldwide. There is strong demand for efficient epidemiological investigation tools to distinguish M. gallisepticum strains in order to control disease. Up to now, multilocus sequence typing (MLST) has been regarded as gold standard for genotyping bacteria due to its good reproducibility and high discriminatory power. The aim of this study was to develop an MLST assay which can determine phylogenetic distances between M. gallisepticum strains. After analysing more than 30 housekeeping genes, six loci (atpG, dnaA, fusA, rpoB, ruvB, uvrA) were selected for the MLST assay due to their genomic location and high diversity. Examination of 130 M. gallisepticum strains with this MLST method yielded 57 unique sequence types (STs) with a 0.96 Simpson's index of diversity. Considering the large number of STs and high diversity index, this MLST method was found to be appropriate to discriminate M. gallisepticum strains. In addition, the developed method was shown to be suitable for epidemiological investigations, as it confirmed linkage between related strains from outbreaks in different farms. Besides, MLST also suggested high impact of extensive international trade on the spread of different M. gallisepticum strains. Furthermore this method can be used for differentiation among vaccine and field strains.
鸡毒支原体引起多种鸟类的慢性呼吸道疾病和生殖障碍，给家禽业造成了巨大的经济损失。维持无支原体鸡群是控制感染的最有效方法。为此，全球范围内应用监测系统和活疫苗株疫苗接种计划。为了控制疾病，迫切需要有效的流行病学调查工具来区分鸡毒支原体菌株。到目前为止，由于其良好的重现性和高区分力，多位点序列分型（MLST）已被认为是细菌基因分型的金标准。本研究旨在开发一种 MLST 检测方法，以确定鸡毒支原体菌株之间的系统发育距离。在分析了 30 多个管家基因后，由于其基因组位置和高度多样性，选择了 6 个基因座（atpG、dnaA、fusA、rpoB、ruvB 和 uvrA）用于 MLST 检测。用这种 MLST 方法检测了 130 株鸡毒支原体，产生了 57 个独特的序列型（ST），多样性指数为 0.96。考虑到 ST 的数量多和多样性指数高，发现这种 MLST 方法适合区分鸡毒支原体菌株。此外，该方法还适用于流行病学调查，因为它证实了不同农场暴发的相关菌株之间存在联系。此外，MLST 还表明广泛的国际贸易对不同鸡毒支原体菌株的传播有很大影响。此外，该方法可用于区分疫苗株和田间分离株。
