protein sequence vs protein sequence database

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Customize Results help

This section allows the selection of columns and the number of rows that are displayed in the results table. You can also customize the table after the search has been performed.

Select Visible Columns help

Choose the different columns to be displayed in the table. The more columns added, the wider the table, which may make the browser window scroll horizontally.

Rows Per Page help

Select the number of rows in the table. If the total number of results exceeds this, then results will be paginated. The larger the number, the more work your browser has to do in order to render the table. Over 1000 rows you are likely to get 'slow JavaScript' warnings from your browser.

Sequence Database help

Choose one of the following target databases for your query to be searched against. The databases vary substantially in size and the amount of functional annotation.

Large collections

Annotated and Structures

Metagenomics and Environmental

Representative Sets

Cut-Offs help

There are two different ways of controlling which target sequences match your query.
E-value:Control both significant and reporting thresholds for the entire sequence and each hit, 10≥x>0.
Bit score:Control both significant and reporting thresholds for the entire sequence and each hit, x>0.

  • Significance E-values:
  • Report E-values:
  • Significance bit scores:
  • Report bit scores:
Gap Penalties help

open:sets the gap open probability. The default is 0.02. Values must be ≥ 0 and < 0.5.
extend:sets the gap extend probability. The default is 0.4. Values must be ≥ 0 and < 1.
matrix:the amino acid substitution matrix used for constructing the probability model. The default is BLOSUM62.


Filters help

Under some circumstances, hits can be lost due to the fact a sequence, or regions of a sequence, are omitted due to bias composition. You can turn this filter off, but it will slow down your searches.

Turn off bias composition filter