With this application we
will be able to compare many sequences at a time. Clustal W is the program we
will be using to perform these similarity searches. The program aligns the first
entered sequence to all other sequences entered. Instead of comparing a
sequence with sequences from a database, Clustal W allows us to compare
multiple sequences against one sequence. Like other alignment programs, this
program will score the sequences according to similarity so that a research can
determine homology.
For information pertaining
to Clustal W version 1.8 refer to:
ClustalW 1.8 Online Help File at Baylor College of Medicine
Instructions:
1. Select the ClustalW
1.8 program.
2. Click on the “Most ReadSeq formats accepted” hyperlink to check
acceptable input formats.
You will find for many of these types of applications that the FASTA
format is the easiest to Copy and Paste with.
3. In the first line, type in a greater-than character (‘>’) followed
by a comment or title for the sequence.
Press enter to start a new line
4. The second line should contain the sequence.
5. Select and copy (or type) your nucleotide sequences (or
accession or GI identifiction numbers)
from the FASTA format to empty box.
Select: Highlight your nucleotide sequence by clicking on the left mouse button, holding the button down while dragging the cursor over the region to be highlighted, then release mouse button.
Copy: Use command from the Edit box of the Explorer window or by pressing CTRL + C on the keyboard.
Paste: Paste into the line following the greater-than character (“>”). No specific format required. Use the Paste command from the Edit box of the Explorer window or press CTRL + V on the keyboard.
6. Repeat steps 3-6
until desired number of sequences is entered into the box.
7. Click on the “Align”
button to start the program.
8. Program will list all
the sequences of the organisms closely related to your sequence.
The most similar will be at the top of the list and the less similar sequences will follow.
If you need more assistance,
please refer to the Help section of the program.
When you are ready, click
here to start.
Clustal W
at Baylor College of Medicine (BCM) Search Launcher