When the field "Organism" is left blank, all organisms in the database will be searched. Otherwise only the organism specified by the Taxonomy ID will be searched.

Examples of Taxonomy IDs are:
OrganismTaxonomy ID
Arabidopsis thaliana3702
Escherichia coli562
Saccharomyces cerevisiae 4932
Drosophila melanogaster7227
Mus musculus10090
Homo sapiens9606

Multiple Taxonomy IDs should be separated by space.

For more information, please go to The NCBI Taxonomy Homepage