The default !conversion setting of natural causes SeqNinja to write/read only those items that are “natural” to the receiving/source file type. Changing the setting to full when changing from an annotated format to a featureless format and back again creates auxiliary file(s) to preserve features and comments that would otherwise be lost.

Convert from GenBank and Lasergene (.seq) format to FASTA format:

The setting full can preserve features and comments that would normally be lost when converting from annotated format to FASTA format, then back again. However, full is not suggested in all cases; for instance, it is not recommended when you plan to make sequence modifications (other than substitutions) while the sequence is in FASTA format. When full is selected, SeqNinja outputs three files during conversion from an annotated format to FASTA format:

  • .fasta – This is a standard FASTA file containing sequence reads. When writing FASTA files from a source that contains comments, the FASTA header line includes the first line of comments from the source. For example:

    > NC_010473 LOCUS NC_010473 4686137 bp DNA circular BCT 04-OCT-2012
  • .starff –This file contains tab-delimited feature information from the original annotated file and can be opened and modified using a spreadsheet utility such as Microsoft Excel®. The modified file can be read by SeqNinja, with the following restrictions: 1) Sequences must appear in exactly the same order as in the corresponding FASTA file. 2) The first six columns must remain present in the original order. Subsequent columns contain qualifier values named in the column header, and can be removed or amended, as desired. 3) The modified file must be saved as tab-delimited text, not as an.xls or .xlsx file, and its name must remain unchanged.
  • .fasta.comments – This file contains one comment pertaining to each sequence in the FASTA file, and in the same order. Comments are maintained during file conversions (e.g., a.seq = b.gbk). However, comments are discarded during sequence transformations (e.g., a.gbk = b.gbk + c.gbk).


Convert the saved FASTA file back to GenBank or Lasergene format:

If you used full during the conversion to FASTA, you can convert back to GenBank or Lasergene, using full again, without losing the original features and comments. As long as you keep the auxiliary files in the same folder as the FASTA data file, SeqNinja will automatically place the features and comments back in the GenBank or Lasergene file.

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