Department of Microbiology, Chung-Ang University College of Medicine, Seoul, Korea.
FEMS Microbiol Lett. 2011 Dec;325(1):77-84. doi: 10.1111/j.1574-6968.2011.02414.x. Epub 2011 Oct 24.
Lactococcus garvieae, the pathogenic species in the genus Lactococcus, is recognized as an emerging pathogen in fish, animals, and humans. Despite the widespread distribution and emerging clinical significance of L. garvieae, little is known about the genomic content of this microorganism. Suppression subtractive hybridization was performed to identify the genomic differences between L. garvieae and Lactococcus lactis ssp. lactis, its closest phylogenetic neighbor, and the type species of the genus Lactococcus. Twenty-seven clones were specific to L. garvieae and were highly different from Lactococcus lactis in their nucleotide and protein sequences. Lactococcus garvieae primer sets were subsequently designed for two of these clones corresponding to a pyrH gene and a novel DNA signature for application in the specific detection of L. garvieae. The primer specificities were evaluated relative to three previously described 16S rRNA gene-targeted methods using 32 Lactococcus and closely related strains. Both newly designed primer sets were highly specific to L. garvieae and performed better than did the existing primers. Our findings may be useful for developing more stable and accurate tools for the discrimination of L. garvieae from other closely related species.
garvieae 乳球菌，乳球菌属中的致病性物种，被认为是鱼类、动物和人类中的一种新兴病原体。尽管 garvieae 乳球菌广泛分布且具有明显的临床意义，但人们对这种微生物的基因组内容知之甚少。采用抑制性消减杂交技术，鉴定了与其亲缘关系最近的乳球菌 lactis ssp. lactis（其模式种）和 garvieae 乳球菌之间的基因组差异。27 个克隆物特异性地存在于 garvieae 乳球菌中，其核苷酸和蛋白质序列与 lactococcus lactis 高度不同。随后针对其中两个克隆物设计了 garvieae 乳球菌引物对，它们对应于 pyrH 基因和一个新的 DNA 特征，可用于 garvieae 乳球菌的特异性检测。相对于之前描述的 32 种乳球菌和密切相关的菌株的三种基于 16S rRNA 基因靶向的方法，评估了这两个新设计的引物对的特异性。这两个新设计的引物对均高度特异性地针对 garvieae 乳球菌，性能优于现有的引物。我们的研究结果可能有助于开发更稳定和准确的工具，用于区分 garvieae 乳球菌和其他密切相关的物种。
