16s rRNA的OTU聚类是微生物组学和宏基因组研究的重要手段之一。受到计算能力的制约，目前的16s rRNA的OTU聚类都没有对输入序列进行多序列比对，因而序列之间的距离无法从全局层面考虑变异信息。申请人前期在多序列比对的算法和并行层面取得了一定成果。受此启发，申请人拟研究多序列比对对16s rRNA OTU聚类的影响，进一步在算法和并行技术两个层面提高多序列比对的效率，最终完成受多序列比对指导的16s rRNA的OTU聚类方法和软件。本项目提出的方法，将有助于肠道微生物种群、石油环境和海洋微生物组学的研究。

16s rRNA OTU clustering is one of the most important preprocesses for microbiomics and metagenomics research. Current 16s rRNA OTU clustering algorithms ignore multiple sequence alignment process, since it is time consuming. We have gotten good performance on multiple sequence alignment recently with algorithm improvement and parallel computation. Therefore, we want to try our latest fruits on 16s rRNA OTU clustering, and explore the influence of multiple sequence alignment on 16s rRNA OTU clustering. With the guide of multiple sequence alignment, the performance of 16s rRNA OTU clustering would be improved and it would benefit the research of the gut microbiota, oil & gas microbiota, and the microbial world in the sea.