细菌的分类和鉴定要求高敏感性和高特异性，但随着已测序细菌基因组数据的增加，基于保守基因如16S rRNA的细菌分类和鉴定方法已无法满足要求。迫切需要从细菌基因组资源挖掘细菌种水平基因组特异序列，通过设计特异性PCR引物、DNA芯片探针和宏基因组分析标记序列，用于细菌种水平的快速鉴定。但目前尚无开放的、综合性的细菌种水平基因组特异序列数据库，也无法用现有软件在可接受时间内计算得到。本研究提出采用基于k-mer（长k的DNA短序列）的方法，自主开发高效的特异序列挖掘软件，利用NCBI RefSeq数据库微生物基因组资源，挖掘细菌种水平的基因组特异性的k-mer，并拼接、延伸为细菌基因组特异序列，建立一个开放和综合性的细菌种水平基因组特异序列数据库，为科研工作者提供特异序列检索、在线计算，注释信息可视化和引物设计等功能，从而应用于细菌的快速检测，病原菌监测，宏基因组菌群分析，和比较基因组分析等

Classification and identification of bacteria require high sensitivity and specificity, however, methods based on conserved genes like 16S rRNA genes are hard to meet these needs with fast increase of sequenced bacterial genomes. It’s urgent to find highly sensitive and specific bacterial species-specific genomic sequences by utilizing rich bacterial genomes resources for fast bacterial identification in species level, which can be used to design PCR primers, DNA probes and marker sequences for metagenomics analysis. Nevertheless, these are no existed open and comprehensive bacterial species-specific genomic sequence databases, neither could be efficiently computed with existed tools in acceptable time either. In this study, we propose to develop an efficient k-mer (DNA subsequence of length k) based specific sequence detection software to detect bacterial species-specific k-mers utilizing bacterial genomes resources in NCBI RefSeq database, and build an open and comprehensive bacterial species-specific genomic sequence database with assembled and extended sequence from k-mers, providing functions including searching, online computation, visualization of bacterial species-specific sequences, and PCR primer design. This database provides valuable resource that can be applied in fast identification of bacteria, pathogen monitoring, metagenomics analysis and comparative genomics analysis.