eggNOGmapper

eggNOGmapper is a software tool designed for the functional annotation of protein sequences. It is part of the eggNOG database, which is a comprehensive resource for functional annotation of genes and proteins. The tool uses a hierarchical classification system to assign functional descriptions to proteins based on their sequence similarity to known proteins in the eggNOG database. This classification system includes levels such as COG (Clusters of Orthologous Groups), KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways, and GO (Gene Ontology) terms.

eggNOGmapper works by comparing the input protein sequences to the sequences in the eggNOG database using BLAST (Basic Local Alignment Search Tool). It then assigns the most appropriate functional annotations based on the similarity scores and the hierarchical classification system. The tool can handle large datasets and is optimized for performance, making it suitable for use in high-throughput genomics projects.

One of the key features of eggNOGmapper is its ability to provide functional annotations at multiple levels of granularity. This allows researchers to gain insights into the biological functions of proteins at different levels of detail. The tool also includes options for customizing the annotation process, such as specifying the level of similarity required for annotation or including additional databases for comparison.

eggNOGmapper is widely used in the field of bioinformatics for functional annotation of protein sequences. It is particularly valuable in the analysis of metagenomic data, where the functional potential of microbial communities can be inferred from the annotated proteins. The tool is freely available and can be accessed through the eggNOG website, making it accessible to researchers worldwide.