A novel semi-supervised algorithm for the taxonomic assignment of metagenomic reads.

Background: Taxonomic assignment is a crucial step in a metagenomic project which aims to identify the origin of sequences in an environmental sample. Among the existing methods, since composition-based algorithms are not sufficient for classifying short reads, recent algorithms use only the feature of similarity, or similarity-based combined features. However, those algorithms suffer from the computational expense because the task of similarity search is very time-consuming.