GB2sequin - Prepare GenBank Files for Submission

GB2sequin converts GenBank or EMBL/ENA flat files into the NCBI submission format Sequin. Additionally, it provides a "five-column, tab-delimited feature table" and a FASTA file required for submission through BankIt or the update of an existing GenBank entry. The program was originally designed to prepare revised GeSeq output for NCBI submission. None the less, any GenBank file is accepted by GB2sequin.


Please take a look at our Documentation.

Citations keep this server running. If you use GB2sequin please cite:


Lehwark P and Greiner S (2019) GB2sequin - a file converter preparing custom GenBank files for database submission. Genomics 111: 759-761


Input Files

GenBank/EMBL (required)


Author Submission Template (optional)§


Source Modifier Table (optional)&


Gene Product Specification Table (optional)$


Specify your Sequence - NCBI Standard Parameters as Default






Molecule Type


Complete  Circular



Genetic Code


Location (e.g. Organelle)


Start Conversion Reset

I have read and accept the Disclaimer


§)"Author Submission Templates" can be created at NCBI. If no "Author Submission Templates" is provided GB2sequin will use "Unknown Author" as default.


&)Please provide your "Source Modifier Table" in the source table format, saving a text file with the file extention src (*.src), or as two column, tab-delimited text file (*.txt). See NCBI for details on the controlled vocabulary allowed for source description. This is an optional upload. Sequence source information can also be added manually in Sequin.


$)Please upload your "Gene Product Specification Table" as a two column, tab-delimited text file (*.txt). If povided, GB2sequin will search for the gene name of a given CDS, tRNA, or rRNA (first column), and add or edit its product description (second column) in your annotation. This feature is optional and might be used for the revision of larger genomes.