Suzuki Chise, Kobayashi Miho, Kimoto-Nira Hiromi
NARO Institute of Livestock and Grassland Science.
Biosci Biotechnol Biochem. 2013;77(10):2013-8. doi: 10.1271/bbb.130322. Epub 2013 Oct 7.
To characterize novel variations of exopolysaccharides (EPSs) produced by dairy strains of Lactococcus lactis subsp. lactis and subsp. cremoris, the EPSs of five dairy strains of L. lactis were purified. Sugar composition analysis showed two novel EPSs produced by strains of L. lactis subsp. lactis. One strain produced EPS lacking galactose, and the other produced EPS containing fucose. Among the eps gene clusters of these strains, the highly conserved epsD and its neighboring epsE were sequenced. Sequence and PCR analysis revealed that epsE genes were strain-specific. By Southern blot analysis using epsD, the eps gene cluster in each strain was found to locate to the chromosome or a very large plasmid. This is the first report on the identification of two novel EPSs in L. lactis subsp. lactis. The strains can be detected among other strains by using epsE genes specific to them.
为了表征乳酸乳球菌乳酸亚种和乳脂亚种的乳制品菌株产生的胞外多糖（EPS）的新变体，对五株乳酸乳球菌的EPS进行了纯化。糖组成分析表明，乳酸乳球菌乳酸亚种的菌株产生了两种新的EPS。一株产生的EPS缺乏半乳糖，另一株产生的EPS含有岩藻糖。在这些菌株的eps基因簇中，对高度保守的epsD及其相邻的epsE进行了测序。序列和PCR分析表明，epsE基因具有菌株特异性。通过使用epsD进行Southern印迹分析，发现每个菌株中的eps基因簇定位于染色体或一个非常大的质粒上。这是关于在乳酸乳球菌乳酸亚种中鉴定两种新EPS的首次报道。通过使用特定于它们的epsE基因，可以在其他菌株中检测到这些菌株。
