Filter Protein Sequence

This tool removes any non-protein characters from a string of text representing an amino acid sequence. It provides options for which characters to filter out, what characters -if any- to substitute the removed characters with, and what case (upper or lower) to output the resulting string in. The tool also determines whether or not the provided amino acid string is valid based on the filtering criteria selected under the filter criteria.

Filter Criteria:

Substiture Character:

Output Case (upper/lower):

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References

This online resource may be cited as follows

MLA	"Quest Calculate™ Filter Protein Sequence." AAT Bioquest, Inc., 22 Dec. 2025, https://www.aatbio.com/tools/quick-calculator/filter-protein.
APA	AAT Bioquest, Inc. (2025, December 22). Quest Calculate™ Filter Protein Sequence. AAT Bioquest. https://www.aatbio.com/tools/quick-calculator/filter-protein.
BibTeX	EndNote	RefMan

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