An UPGMA dendrogram was constructed by START 2.0 software using the unweighted pair-group method and the arithmetic average method (UPGMA). The split decomposition was done with SplitsTree and START 2.0 software on the MLST

website ( http://​eburst.​mlst.​net/​). LEE011 chemical structure Minimum-spanning tree analysis of the STs from all isolates was done using Prims’s algorithm in the BioNumerics software according to region and source separation (version 6.0, Applied-Maths, Sint Maartens-Latem, Belgium). Acknowledgements This research was supported by National Natural Science Foundation of China (Grant No. SN-38 31025019), Hi-Tech Research and Development Program of China (863 Planning, Grant No.2011AA100902), Synergetic Innovation Center of Food Safety and Nutrition, the China Agriculture Research System( Grant No.CARS-37), the Special Fund for Agro-scientific Research in the Public Interest (Grant No. 201303085), the Open Projects of Inner Mongolia Natural Science Foundation (No. 20102010), the Natural Science Foundation of Inner Mongolia (No. 2013MS1205; 2012MS1207), the Scientific Research Projects of Institution of Higher Education in Inner Mongolia (Grant No. NJZY12096). Electronic supplementary material Additional file 1: Table S1: Allelic profiles of 50 Leuconostoc lactis isolates. (DOC 106 KB) References

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